shared memory deallocation Post: 2803

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LEARN ABOUT FREEBSD

ipcrm

IPCRM(1)						    BSD General Commands Manual 						  IPCRM(1)

NAME

     ipcrm -- remove the specified message queues, semaphore sets, and shared segments

SYNOPSIS

     ipcrm [-W] [-v] [-q msqid] [-m shmid] [-s semid] [-Q msgkey] [-M shmkey] [-S semkey] ...

DESCRIPTION

     The ipcrm utility removes the specified message queues, semaphores and shared memory segments.  These System V IPC objects can be specified
     by their creation ID or any associated key.

     The following options are generic:

     -v      If specified once with -W or with -1 for an object, it will show all removed objects.  If specified twice with -W or with -1 for an
	     objects, it will show all removed objects and all failed removals.

     -W      Try to wipe all specified message queues, semaphores and shared memory segments.

     -y      Use the kvm(3) interface instead of the sysctl(3) interface to extract the required information.  If ipcrm is to operate on the run-
	     ning system, using kvm(3) will require read privileges to /dev/kmem.

     The following options are used to specify which IPC objects will be removed.  Any number and combination of these options can be used:

     -q msqid
	     Remove the message queue associated with the ID msqid from the system.

     -m shmid
	     Mark the shared memory segment associated with ID shmid for removal.  This marked segment will be destroyed after the last detach.

     -s semid
	     Remove the semaphore set associated with ID semid from the system.

     -Q msgkey
	     Remove the message queue associated with key msgkey from the system.

     -M shmkey
	     Mark the shared memory segment associated with key shmkey for removal.  This marked segment will be destroyed after the last detach.

     -S semkey
	     Remove the semaphore set associated with key semkey from the system.

     The identifiers and keys associated with these System V IPC objects can be determined by using ipcs(1).  If the identifier or the key is -1,
     it will remove all these objects.

SEE ALSO

     ipcs(1)

HISTORY

     The wiping of all System V IPC objects was first implemented in FreeBSD 6.4 and 7.1.

AUTHORS

     The original author was Adam Glass.  The wiping of all System V IPC objects was thought up by Callum Gibson and extended and implemented by
     Edwin Groothuis.

BSD
								 December 12, 2007							       BSD

10 More Discussions You Might Find Interesting

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Shared memory shortage but lots of unused memory

Discussion started by: cjcamaro

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Discussion started by: vijaya2006

3. Programming

Memory Deallocation Enquery

Discussion started by: zzz_zzz

4. Programming

help with shared memory

Discussion started by: ddx08