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Shared memory in linux
Post 302405882 by Corona688 on Saturday 20th of March 2010 12:27:50 PM
03-20-2010
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LEARN ABOUT DEBIAN
shm
shm.h(3HEAD) Headers shm.h(3HEAD) NAME
shm.h, shm - shared memory facility SYNOPSIS
#include <sys/shm.h> DESCRIPTION
The <sys/shm.h> header defines the following symbolic constants: SHM_RDONLY attach read-only (else read-write) SHM_RND round attach address to SHMLBA The <sys/shm.h> header defines the following symbolic value: SHMLBA segment low boundary address multiple The following data types are defined through typedef: shmatt_t Unsigned integer used for the number of current attaches that must be able to store values at least as large as a type unsigned short. The shmid_ds structure contains the following members: struct ipc_perm shm_perm /* operation permission structure */ size_t shm_segsz /* size of segment in bytes */ pid_t shm_lpid /* process ID of last shared memory operation */ pid_t shm_cpid /* process ID of creator */ shmatt_t shm_nattch /* number of current attaches */ time_t shm_atime /* time of last shmat() */ time_t shm_dtime /* time of last shmdt() */ time_t shm_ctime /* time of last change by shmctl() */ The pid_t, time_t, key_t, and size_t types are defined as described in <sys/types.h>. See types.h(3HEAD). In addition, all of the symbols from <sys/ipc.h> are defined when this header is included. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
shmctl(2), shmget(2), shmop(2), ipc.h(3HEAD), types.h(3HEAD), attributes(5), standards(5) SunOS 5.10 10 Sep 2004 shm.h(3HEAD)