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