IPC.H(3HEAD) Headers IPC.H(3HEAD)

NAME

ipc.h, ipc - XSI interprocess communication access structure

SYNOPSIS

#include <sys/ipc.h>

DESCRIPTION

The <sys/ipc.h> header is used by three mechanisms for interprocess
communication (IPC): messages, semaphores, and shared memory. All use
a common structure type, ipc_perm, to pass information used in
determining permission to perform an IPC operation.


The ipc_perm structure contains the following members:

uid_t uid /* owner's user ID */
gid_t gid /* owner's group ID */
uid_t cuid /* creator's user ID */
gid_t cgid /* creator's group ID */
mode_t mode /* read/write permission


The uid_t, gid_t, mode_t, and key_t types are defined as described in
<sys/types.h>. See types.h(3HEAD).


Definitions are provided for the constants listed below.


Mode bits:

IPC_CREAT
Create entry if key does not exist.


IPC_EXCL
Fail if key exists.


IPC_NOWAIT
Error if request must wait.


Keys:

IPC_PRIVATE
Private key.


Control commands:

IPC_RMID
Remove identifier.


IPC_SET
Set options.


IPC_STAT
Get options.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+

SEE ALSO

ftok(3C), types.h(3HEAD), attributes(7), standards(7)

September 10, 2004 IPC.H(3HEAD)