shmem_startup_hook

Description

Now give loadable modules a chance to set up their shmem allocations

Interface type

shmem_startup_hook_type

Header

src/include/storage/ipc.h

Subsystem

Startup and shared memory

Initial value

NULL (no hook installed)

C interface

typedef void (*shmem_startup_hook_type) (void);
extern PGDLLIMPORT shmem_startup_hook_type shmem_startup_hook;

Call sites

src/backend/storage/ipc/ipci.c:191

src/backend/storage/ipc/ipci.c:249

Core call context: src/backend/storage/ipc/ipci.c:185–199

	CreateOrAttachShmemStructs();

	/*
	 * Now give loadable modules a chance to set up their shmem allocations
	 */
	if (shmem_startup_hook)
		shmem_startup_hook();
}
#endif

/*
 * CreateSharedMemoryAndSemaphores
 *		Creates and initializes shared memory and semaphores.
 */
void

Core call context: src/backend/storage/ipc/ipci.c:243–257

	dsm_postmaster_startup(shim);

	/*
	 * Now give loadable modules a chance to set up their shmem allocations
	 */
	if (shmem_startup_hook)
		shmem_startup_hook();
}

/*
 * Initialize various subsystems, setting up their data structures in
 * shared memory.
 *
 * This is called by the postmaster or by a standalone backend.
 * It is also called by a backend forked from the postmaster in the

Related entries

• shared_preload_libraries

Documentation and source

• Interface declaration
• Core definition
• Call sites

Related entries

• shmem_request_hookshmem_request_hook