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IPCRM(1)			 User Commands			      IPCRM(1)

       ipcrm - remove certain IPC resources

       ipcrm [options]

       ipcrm {shm|msg|sem} id...

       ipcrm removes System V interprocess communication (IPC) objects and as-
       sociated	data structures	from the system.  In order to delete such  ob-
       jects, you must be superuser, or	the creator or owner of	the object.

       System V	IPC objects are	of three types:	shared memory, message queues,
       and semaphores.	Deletion of a message queue or semaphore object	is im-
       mediate	(regardless  of	whether	any process still holds	an IPC identi-
       fier for	the object).  A	shared memory object is	only removed after all
       currently  attached  processes have detached (shmdt(2)) the object from
       their virtual address space.

       Two syntax styles are supported.	 The old Linux historical syntax spec-
       ifies  a	three-letter keyword indicating	which class of object is to be
       deleted,	followed by one	or more	IPC identifiers	for  objects  of  this

       The  SUS-compliant  syntax allows the specification of zero or more ob-
       jects of	all three types	in a single command line, with objects	speci-
       fied either by key or by	identifier (see	below).	 Both keys and identi-
       fiers may be specified in decimal, hexadecimal (specified with an  ini-
       tial '0x' or '0X'), or octal (specified with an initial '0').

       -M, --shmem-key shmkey
	      Remove  the  shared memory segment created with shmkey after the
	      last detach is performed.

       -m, --shmem-id shmid
	      Remove the shared	memory segment identified by shmid  after  the
	      last detach is performed.

       -Q, --queue-key msgkey
	      Remove the message queue created with msgkey.

       -q, --queue-id msgid
	      Remove the message queue identified by msgid.

       -S, --semaphore-key semkey
	      Remove the semaphore created with	semkey.

       -s, --semaphore-id semid
	      Remove the semaphore identified by semid.

       -a, --all [shm] [msg] [sem]
	      Remove  all resources.  When an option argument is provided, the
	      removal is performed only	 for  the  specified  resource	types.
	      Warning!	Do not use -a if you are unsure	how the	software using
	      the resources might react	to  missing  objects.	Some  programs
	      create  these  resources at startup and may not have any code to
	      deal with	an unexpected disappearance.

       The details of the removes are described	in shmctl(2),  msgctl(2),  and
       semctl(2).  The identifiers and keys can	be found by using ipcs(1).

       In  its	first  Linux  implementation, ipcrm used the deprecated	syntax
       shown in	the second line	of the	SYNOPSIS.   Functionality  present  in
       other  *nix  implementations  of	ipcrm has since	been added, namely the
       ability to delete resources by key (not just identifier),  and  to  re-
       spect  the  same	 command-line  syntax.	For backward compatibility the
       previous	syntax is still	supported.

       ipcs(1),	 ipcmk(1),   msgctl(2),	  msgget(2),   semctl(2),   semget(2),
       shmctl(2), shmdt(2), shmget(2), ftok(3)

       The  ipcrm  command  is part of the util-linux package and is available
       from Linux Kernel  Archive  <

util-linux			   July	2014			      IPCRM(1)


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