ipcrm(1) — Linux manual page


IPCRM(1)                      User Commands                     IPCRM(1)

NAME         top

       ipcrm - remove certain IPC resources

SYNOPSIS         top

       ipcrm [options]

       ipcrm [shm|msg|sem] ID ...

DESCRIPTION         top

       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
       specified 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

OPTIONS         top

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

           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.

       -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.

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

       -V, --version
           Print version and exit.

NOTES         top

       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         top

       ipcmk(1), ipcs(1), msgctl(2), msgget(2), semctl(2), semget(2),
       shmctl(2), shmdt(2), shmget(2), ftok(3), sysvipc(7)

REPORTING BUGS         top

       For bug reports, use the issue tracker at

AVAILABILITY         top

       The ipcrm command is part of the util-linux package which can be
       downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>. This page
       is part of the util-linux (a random collection of Linux
       utilities) project. Information about the project can be found at
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have
       a bug report for this manual page, send it to
       util-linux@vger.kernel.org. This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2024-06-14. (At that time, the date of the most recent commit
       that was found in the repository was 2024-06-10.) If you discover
       any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page,
       or you have corrections or improvements to the information in
       this COLOPHON (which is not part of the original manual page),
       send a mail to man-pages@man7.org

util-linux 2.39.594-1e0ad      2023-07-19                       IPCRM(1)

Pages that refer to this page: ipcmk(1)ipcs(1)lsipc(1)pcp-ipcs(1)sysvipc(7)