IPCRM linux command manual

IPCRM(8)                Linux Programmer's Manual                  IPCRM(8)

       ipcrm - remove a message queue, semaphore set or shared memory id

       ipcrm [ -M key | -m id | -Q key | -q id | -S key | -s id ] ...

       deprecated usage

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

       ipcrm  removes  System  V interprocess 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').

       -M shmkey
              removes the shared memory segment created with shmkey after the
              last detach is performed.

       -m shmid
              removes the shared memory segment identified by shmid after the
              last detach is performed.

       -Q msgkey
              removes the message queue created with msgkey.

       -q msgid
              removes the message queue identified by msgid.

       -S semkey
              removes the semaphore created with semkey.

       -s semid
              removes the semaphore identified by semid.

       The details of the removes are described in msgctl(2), shmctl(2),  and
       semctl(2).  The identifiers and keys may be found by using ipcs(8).

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

       ipcs(8),  msgctl(2),  msgget(2),  semctl(2),   semget(2),   shmctl(2),
       shmdt(2), shmget(2), ftok(3)

ipcrm                     last change: 19 March 2002                 IPCRM(8)