Shared memory in linux Post: 302405882

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shm.h

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)