{"kind": "tool", "major": "18", "item": {"slug": "ecpg", "name": "ecpg", "name_zh": "", "category": "Client applications", "summary": "ecpg \u2014 embedded SQL C preprocessor", "aliases": ["ecpg"], "content_hash": "42d17ba54eb3df3fe6d60c81df266b3556115000637f31dc1d2f902eb0941556", "versions": {"10": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "10.23"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX or INFORMIX_SE .", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a C preprocessor symbol.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-D symbol"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/10/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/10/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX or INFORMIX_SE .", "signature": "-C mode", "source_url": "/docs/10/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX or INFORMIX_SE ."}, {"names": ["-D symbol"], "summary": "Define a C preprocessor symbol.", "signature": "-D symbol", "source_url": "/docs/10/app-ecpg.html", "description": "Define a C preprocessor symbol."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/10/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/10/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/10/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/10/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/10/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/10/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/10/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/10/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/10/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "label": "10.23", "major": "10", "channel": "historical", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/10/postgresql-10-A4.pdf", "bytes": 12631706, "pages": 2591, "sha256": "34497ab9efb45c5bdf1bd11b9016b5451354feb462fa029cf74557a5fa5fbbc1", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/10/postgresql-10-US.pdf", "bytes": 12531684, "pages": 2724, "sha256": "429cc7133ddf4f97c560aa466dc9caea4b718721a8321e293357037cf0af4733", "built_at": "2026-09-26"}}, "tree": "10", "index": "index.html", "major": "10", "pages": 1085, "release": "10.23", "source_url": "https://ftp.postgresql.org/pub/source/v10.23/postgresql-10.23.tar.bz2", "svg_assets": 0, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, "revision": "f9301feba91e2e2566038a36b8cee0e4402db68989538f88670fddd20b1f78ea", "evidence_kind": "English manual and source declarations", "source_sha256": "94a4b2528372458e5662c18d406629266667c437198160a18cdfd2c4a4d6eee9"}, "sources": [{"url": "/docs/10/app-ecpg.html", "file": "app-ecpg.html", "label": "10.23 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "5554b5a436af6b9ce2dc5f5d4dec18495e5e88465499830fbcf8bd1aab78baa5"}, {"url": "/docs/10/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "e4330732b6acd6c025a1fbdce45574b23d964de847a1b849ea88b98ab628d2e2"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/10/ecpg.html\" title=\"Chapter\u00a035.\u00a0ECPG - Embedded SQL in C\">Chapter\u00a035</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code> or <code class=\"literal\">INFORMIX_SE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em></code></span></dt>\n<dd>\n<p>Define a C preprocessor symbol.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/10/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\">pg_config</span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre></div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX or INFORMIX_SE ."}, {"names": ["-D symbol"], "signature": "-D symbol", "description": "Define a C preprocessor symbol."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "6fe8df3a35e610fc30be149ee21da8510ec98f7dd5ee5712c2b234363732b9d3"}, "11": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "11.22"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a C preprocessor symbol.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-D symbol"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/11/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/11/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/11/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol"], "summary": "Define a C preprocessor symbol.", "signature": "-D symbol", "source_url": "/docs/11/app-ecpg.html", "description": "Define a C preprocessor symbol."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/11/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/11/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/11/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/11/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/11/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/11/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/11/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/11/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/11/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "label": "11.22", "major": "11", "channel": "historical", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/11/postgresql-11-A4.pdf", "bytes": 13057499, "pages": 2732, "sha256": "41d75855e610d0d9b8802b87dc5b080bef8d7e91c7cf69401fbf8d3cf801b4b5", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/11/postgresql-11-US.pdf", "bytes": 12961189, "pages": 2883, "sha256": "6a8899ef36935a5b7ed2b436207564a567a4ef1eb1c2200195876b8de4d4fa30", "built_at": "2026-09-26"}}, "tree": "11", "index": "index.html", "major": "11", "pages": 1125, "release": "11.22", "source_url": "https://ftp.postgresql.org/pub/source/v11.22/postgresql-11.22.tar.bz2", "svg_assets": 0, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, "revision": "53315ddaf3b3f9e6669fd1edc096bbb2cd4a65ea3e836c89e542b43af9ba3a7f", "evidence_kind": "English manual and source declarations", "source_sha256": "2cb7c97d7a0d7278851bbc9c61f467b69c094c72b81740b751108e7892ebe1f0"}, "sources": [{"url": "/docs/11/app-ecpg.html", "file": "app-ecpg.html", "label": "11.22 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "ec6e6ca128d11aa81d66df9586452a96fde7990cb79e8eea24ad22665c52420a"}, {"url": "/docs/11/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "3a30e696058b118a55cc42892c39671d9bae86f77e1024d5ebcc4688ad9ab4c3"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/11/ecpg.html\" title=\"Chapter\u00a036.\u00a0ECPG - Embedded SQL in C\">Chapter\u00a036</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em></code></span></dt>\n<dd>\n<p>Define a C preprocessor symbol.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/11/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\">pg_config</span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol"], "signature": "-D symbol", "description": "Define a C preprocessor symbol."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "f2ddda4cae1716cfa2c86213d397fd2d4273e5f9e21eb8f0ed95e88e6a813451"}, "12": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "12.22"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/12/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/12/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/12/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/12/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/12/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/12/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/12/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/12/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/12/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/12/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/12/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/12/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/12/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "label": "12.22", "major": "12", "channel": "historical", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/12/postgresql-12-A4.pdf", "bytes": 13424351, "pages": 2803, "sha256": "7422cf53fd1939e7a3d2925231a88b0330e468afa5393627cac0ff86158a0621", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/12/postgresql-12-US.pdf", "bytes": 13322565, "pages": 2958, "sha256": "51f3b04e72907fc38512685946223452ea65f84419c60c66241dfa3396035e77", "built_at": "2026-09-26"}}, "tree": "12", "index": "index.html", "major": "12", "pages": 1131, "release": "12.22", "source_url": "https://ftp.postgresql.org/pub/source/v12.22/postgresql-12.22.tar.bz2", "svg_assets": 2, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, "revision": "7a827e97cbfacd7febff75f34443e2043e40723de5b6d8c9d81a9430b65a37e4", "evidence_kind": "English manual and source declarations", "source_sha256": "8df3c0474782589d3c6f374b5133b1bd14d168086edbc13c6e72e67dd4527a3b"}, "sources": [{"url": "/docs/12/app-ecpg.html", "file": "app-ecpg.html", "label": "12.22 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "41252bd4d3552a190709e096e6557ea78a07489e9477ece5382fd54b68589dba"}, {"url": "/docs/12/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "089624dd131f52eea682b304f87a1acb03392ee7bcf78b000699c9b17c7ca22d"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/12/ecpg.html\" title=\"Chapter\u00a035.\u00a0ECPG - Embedded SQL in C\">Chapter\u00a035</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/12/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\">pg_config</span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "13": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "13.23"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/13/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/13/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/13/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/13/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/13/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/13/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/13/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/13/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/13/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/13/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/13/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/13/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/13/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "label": "13.23", "major": "13", "channel": "historical", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/13/postgresql-13-A4.pdf", "bytes": 13843239, "pages": 2826, "sha256": "171cc09f90936dbc1cbd503a98ff07ae72ea58ab9771ff051313f1217737799c", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/13/postgresql-13-US.pdf", "bytes": 13739572, "pages": 2984, "sha256": "48d09c6e197d9db4220f41afe83efe848a8661b1b168d3b89419751ecaf6c24d", "built_at": "2026-09-26"}}, "tree": "13", "index": "index.html", "major": "13", "pages": 1139, "release": "13.23", "source_url": "https://ftp.postgresql.org/pub/source/v13.23/postgresql-13.23.tar.bz2", "svg_assets": 3, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, "revision": "614ee3133270254e476c118cdf6f72af78d4e4b8bbd9b28ed9ab1e14e4e9c0f6", "evidence_kind": "English manual and source declarations", "source_sha256": "6ec3c82726af92b7dec873fa1cdf881eca92a4219787dfad05acb6b10e041fd6"}, "sources": [{"url": "/docs/13/app-ecpg.html", "file": "app-ecpg.html", "label": "13.23 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "4d37bc1eed0d6c61ef43a7db2c87bbdad17c1dfda86ad891bbb7a8e0369594e8"}, {"url": "/docs/13/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "2a16c2982d9803edd4bd6920f76b66083e7f2959182d6a3bcec7ccfbac0a9ad8"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/13/ecpg.html\" title=\"Chapter\u00a035.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a035</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/13/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\">pg_config</span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "14": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "14.24"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/14/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/14/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/14/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/14/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/14/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/14/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/14/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/14/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/14/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/14/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/14/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/14/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/14/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "label": "14.24", "major": "14", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/14/postgresql-14-A4.pdf", "bytes": 14354704, "pages": 2944, "sha256": "8bc6b9dd7b246888bb77f0a5e8c39a2eae52e9926569832669c7d1600becb27c", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/14/postgresql-14-US.pdf", "bytes": 14242178, "pages": 3102, "sha256": "b7ecb5a5f62d8b9f73a69e25a7d26ba285373bc53168a553bff7b77955506db4", "built_at": "2026-09-26"}}, "tree": "14", "index": "index.html", "major": "14", "pages": 1158, "release": "14.24", "source_url": "https://ftp.postgresql.org/pub/source/v14.24/postgresql-14.24.tar.bz2", "svg_assets": 3, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, "revision": "588700d46356d8837c77c7c0a4e71e645fe6535983b8f1830aa8f2e4e41c40ae", "evidence_kind": "English manual and source declarations", "source_sha256": "a7fa7ed3d558172355f51406097a7bd4f6b473be80f311ef7cda96bf383d8897"}, "sources": [{"url": "/docs/14/app-ecpg.html", "file": "app-ecpg.html", "label": "14.24 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "e99a32676a25cc3c5214abb143a82e1428aedeb64b86fc333a34902f15c19a5c"}, {"url": "/docs/14/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "5a13567a052954dfe494dfaab9f50919faa1ae56023930fdbb78d45e53feccde"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/14/ecpg.html\" title=\"Chapter\u00a036.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a036</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/14/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "15": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "15.19"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/15/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/15/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/15/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/15/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/15/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/15/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/15/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/15/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/15/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/15/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/15/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/15/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/15/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "label": "15.19", "major": "15", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/15/postgresql-15-A4.pdf", "bytes": 14609140, "pages": 2987, "sha256": "66228564a4d16efb47d6a914085716ecfe22ca1566db56bc7c3d82f790646d72", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/15/postgresql-15-US.pdf", "bytes": 14495690, "pages": 3153, "sha256": "645a498c2390d47a6223ec74770631185807a19c484edb0fc5a295d9f460bc02", "built_at": "2026-09-26"}}, "tree": "15", "index": "index.html", "major": "15", "pages": 1168, "release": "15.19", "source_url": "https://ftp.postgresql.org/pub/source/v15.19/postgresql-15.19.tar.bz2", "svg_assets": 3, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, "revision": "6af958c6520151fc7697d56e0616b03fb00522c4568158674d452ae0644ba545", "evidence_kind": "English manual and source declarations", "source_sha256": "e1a64a87a46b825b88c082e4518161a47aab53c45694964f8ba1df28f7859f89"}, "sources": [{"url": "/docs/15/app-ecpg.html", "file": "app-ecpg.html", "label": "15.19 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "86f933b4855a4c1e43001e1348adf31c9440352b8cd5c187da39a272c6afe41d"}, {"url": "/docs/15/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "015b2ea2bd205946a55a1b837e735570631bac831c92074a6bf58444f9a3cb98"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/15/ecpg.html\" title=\"Chapter\u00a036.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a036</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/15/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "16": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "16.15"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/16/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/16/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/16/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/16/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/16/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/16/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/16/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/16/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/16/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/16/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/16/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/16/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/16/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "label": "16.15", "major": "16", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/16/postgresql-16-A4.pdf", "bytes": 15282337, "pages": 3055, "sha256": "4bb6c1f63deedac98736d8c4c7bc0fad0ac24e85b07e21ee10411872f06afd06", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/16/postgresql-16-US.pdf", "bytes": 15164148, "pages": 3220, "sha256": "5b6b6166c89991199e144bb0ae34c17a5f29826251dbf19db1abc0df3a3e771b", "built_at": "2026-09-26"}}, "tree": "16", "index": "index.html", "major": "16", "pages": 1169, "release": "16.15", "source_url": "https://ftp.postgresql.org/pub/source/v16.15/postgresql-16.15.tar.bz2", "svg_assets": 3, "source_mode": "en HTML verified against the pinned official archive", "source_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, "revision": "3c21e58b35318021716440e67bb8bafd392b6a2b965a244d90e9e33c99e0bdef", "evidence_kind": "English manual and source declarations", "source_sha256": "c1575341fa7bd40f5274ea465b34390f4dc64cdd0770af327005caaeb9f6b7ed"}, "sources": [{"url": "/docs/16/app-ecpg.html", "file": "app-ecpg.html", "label": "16.15 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "b2e93d175de43f0066354a60940f15f399d7b6b57124eb5cdfa5b869d65d4e83"}, {"url": "/docs/16/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "a28c30c3c0f8783e16d56413a0b6fd39487e336da1683b29b60abf1c229cef26"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/16/ecpg.html\" title=\"Chapter\u00a036.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a036</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/16/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "17": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "17.11"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/17/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/17/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/17/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/17/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/17/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/17/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/17/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/17/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/17/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/17/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/17/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/17/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/17/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "label": "17.11", "major": "17", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/17/postgresql-17-A4.pdf", "bytes": 15521293, "pages": 3099, "sha256": "1991354df0dc89e70ec39328c28988ef8b19c6a93671dab3893650b63e9f4e36", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/17/postgresql-17-US.pdf", "bytes": 15398150, "pages": 3270, "sha256": "07696c8f38abf31babf22d2db337093936e7c472d2af36d050b000c49bbcf52c", "built_at": "2026-09-26"}}, "tree": "17", "index": "index.html", "major": "17", "pages": 1143, "release": "17.11", "source_url": "https://ftp.postgresql.org/pub/source/v17.11/postgresql-17.11.tar.bz2", "svg_assets": 3, "source_mode": "en SGML built with pinned official archive", "source_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, "revision": "58419c9b0dd42cb34c8d53695bb025a7e582edf55ccd4c5bcb1c2c7c71a37487", "evidence_kind": "English manual and source declarations", "source_sha256": "dd27f2b3c59e73ed14aa3324901242bf69a032a6347805f274e6260322d42979"}, "sources": [{"url": "/docs/17/app-ecpg.html", "file": "app-ecpg.html", "label": "17.11 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "6b203f82a7c2221aa35b80e5b27837797cb91443c406c9835596c639e272b426"}, {"url": "/docs/17/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "3194fc72ddad8e2fcba55f8e007f83413cb352146cb65aaa9457a18d0314ee1b"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/17/ecpg.html\" title=\"Chapter\u00a034.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a034</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/17/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "18": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "18.6"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/18/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/18/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/18/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/18/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/18/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/18/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/18/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/18/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/18/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/18/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/18/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/18/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "label": "18.6", "major": "18", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/18/postgresql-18-A4.pdf", "bytes": 15865106, "pages": 3154, "sha256": "19512c405da53f9f7fcf0abba359223aa65f021be025bf3411381918f92e3190", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/18/postgresql-18-US.pdf", "bytes": 15748059, "pages": 3328, "sha256": "facbe6c229e598b872d3d98bef53308f46e06746006fa4590de9a7de9dd46319", "built_at": "2026-09-26"}}, "tree": "18", "index": "index.html", "major": "18", "pages": 1148, "release": "18.6", "source_url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "svg_assets": 3, "source_mode": "en SGML built with pinned official archive", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "revision": "ee8d1a3612338fd9adf250730cb640fcc5233b5491337cc00a316a44e3a0b9f8", "evidence_kind": "English manual and source declarations", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "sources": [{"url": "/docs/18/app-ecpg.html", "file": "app-ecpg.html", "label": "18.6 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "46e369f91d3516a728d286bbeab8bf7500f9e5016436847622154cb3777b5173"}, {"url": "/docs/18/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "68f726af77272fe73a827be2b7b5958d0f2239a6f8ed44264e9d42496bfa4fd0"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/18/ecpg.html\" title=\"Chapter\u00a034.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a034</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/18/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "19": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "19beta4"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/19/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/19/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/19/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/19/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/19/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/19/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/19/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/19/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/19/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/19/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/19/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/19/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/19/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "label": "19beta4", "major": "19", "channel": "preview", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/19/postgresql-19-A4.pdf", "bytes": 16064841, "pages": 3052, "sha256": "4dd099e4125c591128fc5f3ebd02178dc24781f9e5ae629f96d67c4c8547427b", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/19/postgresql-19-US.pdf", "bytes": 15974616, "pages": 3225, "sha256": "61971fa857f0956d47341a0388fa6af9ae10acf691d4b2fc009007d384b0342b", "built_at": "2026-09-26"}}, "tree": "19", "index": "index.html", "major": "19", "pages": 1155, "release": "19beta4", "source_url": "https://ftp.postgresql.org/pub/source/v19beta4/postgresql-19beta4.tar.bz2", "svg_assets": 5, "source_mode": "en SGML built with pinned official archive", "source_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, "revision": "1bbbbf4133d426f0e4304010688d2984c30fb67df0cc3a61b3e37eb3f6f37833", "evidence_kind": "English manual and source declarations", "source_sha256": "83157ee9c599d03b2f7a3d73ef3a56ec24e0e79cc2b3501a64d1364f56398c86"}, "sources": [{"url": "/docs/19/app-ecpg.html", "file": "app-ecpg.html", "label": "19beta4 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "7148d95a0976c580bd128b6d8965b9f35e15011a9efb1dc66386bb3c601a3ef4"}, {"url": "/docs/19/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "c827f460db781b39da305303c88e73729a419cd2b2b9dedb126d8ad5cbf02c95"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/19/ecpg.html\" title=\"Chapter\u00a034.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a034</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/19/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "20": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "20devel"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/devel/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/devel/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/devel/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/devel/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/devel/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/devel/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/devel/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/devel/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/devel/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/devel/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/devel/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/devel/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/devel/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "label": "20devel", "major": "20", "channel": "devel", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/20/postgresql-20-A4.pdf", "bytes": 16030631, "pages": 3052, "sha256": "bd5d82c0ce38fc18f92a0447818a91a193a261776bca1c37564bf9a683e177d0", "built_at": "2026-09-28"}, "US": {"url": "/files/documentation/pdf/20/postgresql-20-US.pdf", "bytes": 15936613, "pages": 3223, "sha256": "d97d9e0db479a02f4234b175f50fcad70c3661619afc8d6df9b9437882e3c299", "built_at": "2026-09-28"}}, "tree": "0", "index": "index.html", "major": "20", "pages": 1156, "release": "20devel", "source_url": "https://ftp.postgresql.org/pub/snapshot/dev/postgresql-snapshot.tar.bz2", "svg_assets": 6, "source_mode": "en SGML built with pinned official archive", "source_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41", "source_snapshot_utc": "26-Sep-2026 20:22"}, "revision": "2eba5e0fd4c3bffb2803247b6cd537878e9d6ee5a6dfbe3c50ece8b421b80918", "evidence_kind": "English manual and source declarations", "source_sha256": "4d3346909b201ac1648232cf290462a7070c119326f56196f1f0253ed80fae41"}, "sources": [{"url": "/docs/devel/app-ecpg.html", "file": "app-ecpg.html", "label": "20devel English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "062168b1a9795fac1c5e94148349b4da07d3ed6c07c01ae24ec350360c5a0a68"}, {"url": "/docs/devel/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "a6c7ba748fa1d9feac5bb7cde41d1d36a1f4c26d5963e07fb103d02918b2a8ca"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/devel/ecpg.html\" title=\"Chapter\u00a034.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a034</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/devel/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}}}, "snapshot": {"facts": [{"label": "Documented executable", "value": "ecpg"}, {"label": "Executable version", "value": "18.6"}, {"label": "Reference inventory", "value": "Client applications"}, {"label": "Option definition groups", "value": "12"}], "tables": [{"key": "options", "rows": [{"summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-c"}}, {"summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-C mode"}}, {"summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-D symbol [= value ]"}}, {"summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-h"}}, {"summary": "Parse system include files as well.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-i"}}, {"summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-I directory"}}, {"summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-o filename"}}, {"summary": "Selects run-time behavior. Option can be one of the following:", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-r option"}}, {"summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-t"}}, {"summary": "Print additional information including the version and the \"include\" path.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-v"}}, {"summary": "Print the ecpg version and exit.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "--version"}}, {"summary": "Show help about ecpg command line arguments, and exit.", "signature": {"url": "/docs/18/app-ecpg.html", "text": "-? --help"}}], "title": "Documented options", "columns": [{"key": "signature", "label": "Option and arguments"}, {"key": "summary", "label": "Description"}]}], "options": [{"names": ["-c"], "summary": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE .", "signature": "-c", "source_url": "/docs/18/app-ecpg.html", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "summary": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE .", "signature": "-C mode", "source_url": "/docs/18/app-ecpg.html", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "summary": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .", "signature": "-D symbol [= value ]", "source_url": "/docs/18/app-ecpg.html", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "summary": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.", "signature": "-h", "source_url": "/docs/18/app-ecpg.html", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "summary": "Parse system include files as well.", "signature": "-i", "source_url": "/docs/18/app-ecpg.html", "description": "Parse system include files as well."}, {"names": ["-I directory"], "summary": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order.", "signature": "-I directory", "source_url": "/docs/18/app-ecpg.html", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "summary": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output.", "signature": "-o filename", "source_url": "/docs/18/app-ecpg.html", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "summary": "Selects run-time behavior. Option can be one of the following:", "signature": "-r option", "source_url": "/docs/18/app-ecpg.html", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "summary": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued.", "signature": "-t", "source_url": "/docs/18/app-ecpg.html", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "summary": "Print additional information including the version and the \"include\" path.", "signature": "-v", "source_url": "/docs/18/app-ecpg.html", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "summary": "Print the ecpg version and exit.", "signature": "--version", "source_url": "/docs/18/app-ecpg.html", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "summary": "Show help about ecpg command line arguments, and exit.", "signature": "-? --help", "source_url": "/docs/18/app-ecpg.html", "description": "Show help about ecpg command line arguments, and exit."}], "related": [], "release": {"ref": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "label": "18.6", "major": "18", "channel": "stable", "manifest": {"pdf": {"A4": {"url": "/files/documentation/pdf/18/postgresql-18-A4.pdf", "bytes": 15865106, "pages": 3154, "sha256": "19512c405da53f9f7fcf0abba359223aa65f021be025bf3411381918f92e3190", "built_at": "2026-09-26"}, "US": {"url": "/files/documentation/pdf/18/postgresql-18-US.pdf", "bytes": 15748059, "pages": 3328, "sha256": "facbe6c229e598b872d3d98bef53308f46e06746006fa4590de9a7de9dd46319", "built_at": "2026-09-26"}}, "tree": "18", "index": "index.html", "major": "18", "pages": 1148, "release": "18.6", "source_url": "https://ftp.postgresql.org/pub/source/v18.6/postgresql-18.6.tar.bz2", "svg_assets": 3, "source_mode": "en SGML built with pinned official archive", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "revision": "ee8d1a3612338fd9adf250730cb640fcc5233b5491337cc00a316a44e3a0b9f8", "evidence_kind": "English manual and source declarations", "source_sha256": "555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f"}, "sources": [{"url": "/docs/18/app-ecpg.html", "file": "app-ecpg.html", "label": "18.6 English manual \u00b7 app-ecpg.html", "anchor": "", "sha256": "46e369f91d3516a728d286bbeab8bf7500f9e5016436847622154cb3777b5173"}, {"url": "/docs/18/reference-client.html", "file": "reference-client.html", "label": "Client applications inventory", "anchor": "", "sha256": "68f726af77272fe73a827be2b7b5958d0f2239a6f8ed44264e9d42496bfa4fd0"}], "sections": [], "synopsis": ["ecpg [ option ...] file ..."], "signature": "ecpg [ option ...] file ...", "description": ["ecpg \u2014 embedded SQL C preprocessor"], "environment": [], "manual_html": "<div><div class=\"refentry\" id=\"APP-ECPG\">\n<div class=\"titlepage\"></div>\n<div class=\"refnamediv\">\n<h2><span class=\"refentrytitle\"><span class=\"application\">ecpg</span></span></h2>\n<p><span class=\"application\">ecpg</span> \u2014 embedded SQL C preprocessor</p>\n</div>\n<div class=\"refsynopsisdiv\">\n<h2>Synopsis</h2>\n<div class=\"cmdsynopsis\">\n<p id=\"id-1.9.4.8.4.1\"><code class=\"command\">ecpg</code> [<em class=\"replaceable\"><code>option</code></em>...] <em class=\"replaceable\"><code>file</code></em>...</p>\n</div>\n</div>\n<div class=\"refsect1\" id=\"APP-ECPG-DESCRIPTION\">\n<h2>Description</h2>\n<p><code class=\"command\">ecpg</code> is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain.</p>\n<p><code class=\"command\">ecpg</code> will convert each input file given on the command line to the corresponding C output file. If an input file name does not have any extension, <code class=\"filename\">.pgc</code> is assumed. The file's extension will be replaced by <code class=\"filename\">.c</code> to construct the output file name. But the output file name can be overridden using the <code class=\"option\">-o</code> option.</p>\n<p>If an input file name is just <code class=\"literal\">-</code>, <code class=\"command\">ecpg</code> reads the program from standard input (and writes to standard output, unless that is overridden with <code class=\"option\">-o</code>).</p>\n<p>This reference page does not describe the embedded SQL language. See <a class=\"xref\" href=\"/docs/18/ecpg.html\" title=\"Chapter\u00a034.\u00a0ECPG \u2014 Embedded SQL in C\">Chapter\u00a034</a> for more information on that topic.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.6\">\n<h2>Options</h2>\n<p><code class=\"command\">ecpg</code> accepts the following command-line arguments:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">-c</code></span></dt>\n<dd>\n<p>Automatically generate certain C code from SQL code. Currently, this works for <code class=\"literal\">EXEC SQL TYPE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-C <em class=\"replaceable\"><code>mode</code></em></code></span></dt>\n<dd>\n<p>Set a compatibility mode. <em class=\"replaceable\"><code>mode</code></em> can be <code class=\"literal\">INFORMIX</code>, <code class=\"literal\">INFORMIX_SE</code>, or <code class=\"literal\">ORACLE</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-D <em class=\"replaceable\"><code>symbol</code></em>[=<em class=\"replaceable\"><code>value</code></em>]</code></span></dt>\n<dd>\n<p>Define a preprocessor symbol, equivalently to the <code class=\"command\">EXEC SQL DEFINE</code> directive. If no <em class=\"replaceable\"><code>value</code></em> is specified, the symbol is defined with the value <code class=\"literal\">1</code>.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-h</code></span></dt>\n<dd>\n<p>Process header files. When this option is specified, the output file extension becomes <code class=\"literal\">.h</code> not <code class=\"literal\">.c</code>, and the default input file extension is <code class=\"literal\">.pgh</code> not <code class=\"literal\">.pgc</code>. Also, the <code class=\"option\">-c</code> option is forced on.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-i</code></span></dt>\n<dd>\n<p>Parse system include files as well.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-I <em class=\"replaceable\"><code>directory</code></em></code></span></dt>\n<dd>\n<p>Specify an additional include path, used to find files included via <code class=\"literal\">EXEC SQL INCLUDE</code>. Defaults are <code class=\"filename\">.</code> (current directory), <code class=\"filename\">/usr/local/include</code>, the <span class=\"productname\">PostgreSQL</span> include directory which is defined at compile time (default: <code class=\"filename\">/usr/local/pgsql/include</code>), and <code class=\"filename\">/usr/include</code>, in that order.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-o <em class=\"replaceable\"><code>filename</code></em></code></span></dt>\n<dd>\n<p>Specifies that <code class=\"command\">ecpg</code> should write all its output to the given <em class=\"replaceable\"><code>filename</code></em>. Write <code class=\"literal\">-o -</code> to send all output to standard output.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-r <em class=\"replaceable\"><code>option</code></em></code></span></dt>\n<dd>\n<p>Selects run-time behavior. <em class=\"replaceable\"><code>Option</code></em> can be one of the following:</p>\n<div class=\"variablelist\">\n<dl class=\"variablelist\">\n<dt><span class=\"term\"><code class=\"option\">no_indicator</code></span></dt>\n<dd>\n<p>Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">prepare</code></span></dt>\n<dd>\n<p>Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">questionmarks</code></span></dt>\n<dd>\n<p>Allow question mark as placeholder for compatibility reasons. This used to be the default long ago.</p>\n</dd>\n</dl>\n</div>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-t</code></span></dt>\n<dd>\n<p>Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when <code class=\"command\">EXEC SQL COMMIT</code> is issued.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-v</code></span></dt>\n<dd>\n<p>Print additional information including the version and the \"include\" path.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">--version</code></span></dt>\n<dd>\n<p>Print the <span class=\"application\">ecpg</span> version and exit.</p>\n</dd>\n<dt><span class=\"term\"><code class=\"option\">-?</code><br></span><span class=\"term\"><code class=\"option\">--help</code></span></dt>\n<dd>\n<p>Show help about <span class=\"application\">ecpg</span> command line arguments, and exit.</p>\n</dd>\n</dl>\n</div>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.7\">\n<h2>Notes</h2>\n<p>When compiling the preprocessed C code files, the compiler needs to be able to find the <span class=\"application\">ECPG</span> header files in the <span class=\"productname\">PostgreSQL</span> include directory. Therefore, you might have to use the <code class=\"option\">-I</code> option when invoking the compiler (e.g., <code class=\"literal\">-I/usr/local/pgsql/include</code>).</p>\n<p>Programs using C code with embedded SQL have to be linked against the <code class=\"filename\">libecpg</code> library, for example using the linker options <code class=\"literal\">-L/usr/local/pgsql/lib -lecpg</code>.</p>\n<p>The value of either of these directories that is appropriate for the installation can be found out using <a class=\"xref\" href=\"/docs/18/app-pgconfig.html\" title=\"pg_config\"><span class=\"refentrytitle\"><span class=\"application\">pg_config</span></span></a>.</p>\n</div>\n<div class=\"refsect1\" id=\"id-1.9.4.8.8\">\n<h2>Examples</h2>\n<p>If you have an embedded SQL C source file named <code class=\"filename\">prog1.pgc</code>, you can create an executable program using the following sequence of commands:</p>\n<pre class=\"programlisting\">ecpg prog1.pgc\ncc -I/usr/local/pgsql/include -c prog1.c\ncc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg\n</pre>\n</div>\n</div></div>", "manual_path": "app-ecpg.html", "comparison_data": {"options": [{"names": ["-c"], "signature": "-c", "description": "Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE ."}, {"names": ["-C mode"], "signature": "-C mode", "description": "Set a compatibility mode. mode can be INFORMIX , INFORMIX_SE , or ORACLE ."}, {"names": ["-D symbol [= value ]"], "signature": "-D symbol [= value ]", "description": "Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 ."}, {"names": ["-h"], "signature": "-h", "description": "Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on."}, {"names": ["-i"], "signature": "-i", "description": "Parse system include files as well."}, {"names": ["-I directory"], "signature": "-I directory", "description": "Specify an additional include path, used to find files included via EXEC SQL INCLUDE . Defaults are . (current directory), /usr/local/include , the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include ), and /usr/include , in that order."}, {"names": ["-o filename"], "signature": "-o filename", "description": "Specifies that ecpg should write all its output to the given filename . Write -o - to send all output to standard output."}, {"names": ["-r option"], "signature": "-r option", "description": "Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago."}, {"names": ["-t"], "signature": "-t", "description": "Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued."}, {"names": ["-v"], "signature": "-v", "description": "Print additional information including the version and the \"include\" path."}, {"names": ["--version"], "signature": "--version", "description": "Print the ecpg version and exit."}, {"names": ["-?", "--help"], "signature": "-? --help", "description": "Show help about ecpg command line arguments, and exit."}], "synopsis": ["ecpg [ option ...] file ..."], "environment": []}, "comparison_hash": "9b115ab9dbd18516028622d20fe8fe477e01f88cb80ad0615213dea618875d6d"}, "comparison": {"left": "11", "right": "12", "status": "changed", "diff": "--- PostgreSQL 11\n+++ PostgreSQL 12\n@@ -16,11 +16,11 @@\n       \"signature\": \"-C mode\"\n     },\n     {\n-      \"description\": \"Define a C preprocessor symbol.\",\n+      \"description\": \"Define a preprocessor symbol, equivalently to the EXEC SQL DEFINE directive. If no value is specified, the symbol is defined with the value 1 .\",\n       \"names\": [\n-        \"-D symbol\"\n+        \"-D symbol [= value ]\"\n       ],\n-      \"signature\": \"-D symbol\"\n+      \"signature\": \"-D symbol [= value ]\"\n     },\n     {\n       \"description\": \"Process header files. When this option is specified, the output file extension becomes .h not .c , and the default input file extension is .pgh not .pgc . Also, the -c option is forced on.\","}}