This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
sys/ipc.h — XSI interprocess communication access structure
header is used by three mechanisms for XSI
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.
header shall define the ipc_perm
which shall include 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.
header shall define the uid_t
, and key_t
types as described in
header shall define the following symbolic
- Create entry if key does not exist.
- Fail if key exists.
- Error if request must wait.
- Private key.
- Remove identifier.
- Set options.
- Get options.
The following shall be declared as a function and may also be defined as a
macro. A function prototype shall be provided.
The following sections are informative.
key_t ftok(const char *, int);
The System Interfaces volume of POSIX.1‐2008, ftok()
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2013 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
7, Copyright (C) 2013 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013
Technical Corrigendum 1 applied.) In the event of any discrepancy between this
version and the original IEEE and The Open Group Standard, the original IEEE
and The Open Group Standard is the referee document. The original Standard can
be obtained online at http://www.unix.org/online.html .
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