This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
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implemented on Linux.
ipcrm — remove an XSI message queue, semaphore set, or shared memory
ipcrm [−q msgid|−Q msgkey|−s semid|−S semkey|−m shmid|−M shmkey]...
utility shall remove zero or more message queues, semaphore
sets, or shared memory segments. The interprocess communication facilities to
be removed are specified by the options.
Only a user with appropriate privileges shall be allowed to remove an
interprocess communication facility that was not created by or owned by the
user invoking ipcrm
utility shall conform to the Base Definitions volume of
POSIX.1‐2008, Section 12.2
, Utility Syntax Guidelines
The following options shall be supported:
- −q msgid
- Remove the message queue identifier msgid from the
system and destroy the message queue and data structure associated with
- −m shmid
- Remove the shared memory identifier shmid from the
system. The shared memory segment and data structure associated with it
shall be destroyed after the last detach.
- −s semid
- Remove the semaphore identifier semid from the
system and destroy the set of semaphores and data structure associated
- −Q msgkey
- Remove the message queue identifier, created with key
msgkey, from the system and destroy the message queue and data
structure associated with it.
- −M shmkey
- Remove the shared memory identifier, created with key
shmkey, from the system. The shared memory segment and data
structure associated with it shall be destroyed after the last
- −S semkey
- Remove the semaphore identifier, created with key
semkey, from the system and destroy the set of semaphores and data
structure associated with it.
The following environment variables shall affect the execution of ipcrm
- Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions volume of
POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization variables used to
determine the values of locale categories.)
- If set to a non-empty string value, override the values of
all the other internationalization variables.
- Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte as opposed to
multi-byte characters in arguments).
Determine the locale that should be used to affect the format and contents
of diagnostic messages written to standard error.
- Determine the location of message catalogs for the
processing of LC_MESSAGES.
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
- Successful completion.
- An error occurred.
The following sections are informative.
The Base Definitions volume of POSIX.1‐2008, Chapter 8
, Section 12.2
, Utility Syntax
The System Interfaces volume of POSIX.1‐2008, msgctl()
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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