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 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 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.  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

       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/⟩.