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
   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

   ipcs(1),  ipcmk(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  ftp://ftp.kernel.org/pub/linux/utils/util-
   linux/.

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