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(7) 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(7),
standards(7) September 10, 2004 SHM.H(3HEAD)
