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 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.

       -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         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)

AVAILABILITY         top

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

COLOPHON         top

       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
       2021-03-21.  (At that time, the date of the most recent commit
       that was found in the repository was 2021-03-19.)  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                      July 2014                       IPCRM(1)

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