IPCRM(1)							   User Commands							  IPCRM(1)

NAME

       ipcrm - remove certain IPC resources

SYNOPSIS

       ipcrm [options]

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

DESCRIPTION

       ipcrm  removes  System V inter-process communication (IPC) objects and associated data structures from the system.  In order to delete such
       objects, 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
       immediate  (regardless  of whether any process still holds an IPC identifier 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 specifies a three-letter keyword indicating which class of object  is	to
       be deleted, followed by one or more IPC identifiers for objects of this type.

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

       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).

OPTIONS

       -a, --all [shm] [msg] [sem]
	      Remove  all  resources.  When an option argument is provided, the removal is performed only for the specified resource types.  Warn-
	      ing!  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.

       -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.

       -V, --version
	      Display version information and exit.

       -h, --help
	      Display help text and exit.

NOTES

       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
       respect the same command-line syntax.  For backward compatibility the previous syntax is still supported.

SEE ALSO

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

AVAILABILITY

       The  ipcrm  command  is	part  of the util-linux package and is available from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils
       /util-linux/>.

util-linux							     July 2014								  IPCRM(1)