/****************************************************** The interface to the operating system shared memory primitives (c) 1995 Innobase Oy Created 9/23/1995 Heikki Tuuri *******************************************************/ #ifndef os0shm_h #define os0shm_h #include "univ.i" typedef void* os_shm_t; /******************************************************************** Creates an area of shared memory. It can be named so that different processes may access it in the same computer. If an area with the same name already exists, returns a handle to that area (where the size of the area is not changed even if this call requests a different size). To use the area, it first has to be mapped to the process address space by os_shm_map. */ os_shm_t os_shm_create( /*==========*/ /* out, own: handle to the shared memory area, NULL if error */ ulint size, /* in: area size < 4 GB */ char* name); /* in: name of the area as a null-terminated string */ /*************************************************************************** Frees a shared memory area. The area can be freed only after it has been unmapped in all the processes where it was mapped. */ ibool os_shm_free( /*========*/ /* out: TRUE if success */ os_shm_t shm); /* in, own: handle to a shared memory area */ /*************************************************************************** Maps a shared memory area in the address space of a process. */ void* os_shm_map( /*=======*/ /* out: address of the area, NULL if error */ os_shm_t shm); /* in: handle to a shared memory area */ /*************************************************************************** Unmaps a shared memory area from the address space of a process. */ ibool os_shm_unmap( /*=========*/ /* out: TRUE if succeed */ void* addr); /* in: address of the area */ #ifndef UNIV_NONINL #include "os0shm.ic" #endif #endif