Historical version. PostgreSQL 7.3 has reached end of support. See the current manual.
1.8. libpq Tracing Functions
PQtraceEnable tracing of the frontend/backend communication to a debugging file stream.void PQtrace(PGconn *conn FILE *debug_port)PQuntraceDisable tracing started byPQtrace.void PQuntrace(PGconn *conn)
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