{"Entry":{"collection":"hook","key":"shmem_startup_hook","name":"shmem_startup_hook","aliases":[],"metadata":{"aliases":[],"category":"Startup and shared memory","content_hash":"ebe8d9817c2337f6f1564f254f021f50ffd04f903a37d58eeee6956e9f8acaab","imported_at":"2026-09-30T17:44:22.45807+08:00","name":"shmem_startup_hook","name_zh":"shmem_startup_hook","slug":"shmem_startup_hook","summary":"Now give loadable modules a chance to set up their shmem allocations"}},"Definition":{"Collection":"hook","Key":"shmem_startup_hook","SourceDatabase":"center","Version":"18","SourceTable":"hook","SourceKey":"shmem_startup_hook","SourceRevision":"753057e340da8f22e57c9a409ea7a235fd6a46bd","Facts":{"description":["Now give loadable modules a chance to set up their shmem allocations"],"facts":[{"label":"Interface type","value":"shmem_startup_hook_type"},{"label":"Header","value":"src/include/storage/ipc.h"},{"label":"Subsystem","value":"Startup and shared memory"},{"label":"Initial value","value":"NULL (no 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setting up their data structures in\n * shared memory.\n *\n * This is called by the postmaster or by a standalone backend.\n * It is also called by a backend forked from the postmaster in the","paragraphs":[],"title":"Core call context: src/backend/storage/ipc/ipci.c:243–257"}],"signature":"typedef void (*shmem_startup_hook_type) (void);\nextern PGDLLIMPORT shmem_startup_hook_type shmem_startup_hook;","sources":[{"label":"Interface declaration","path":"src/include/storage/ipc.h","sha256":"7eaed5df20e9c94832bf72b758512f55113d727b3cfc426cf7642b2a8ca89334","url":"https://github.com/postgres/postgres/blob/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/include/storage/ipc.h#L22"},{"label":"Core definition","path":"src/backend/storage/ipc/ipci.c","sha256":"2fa09c75851a35bfb974c97e64f82505e236e56cf480ded7ed7a632cec39d77c","url":"https://github.com/postgres/postgres/blob/753057e340da8f22e57c9a409ea7a235fd6a46bd/src/backend/storage/ipc/ipci.c#L58"},{"label":"Call 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