03-27-2007
semaphores
Hi Friends,
If i execute this command it comes back with 300 lines:
ipcs|grep cerebrus >>> i would like to clear the semaphores but ipcrm can remove one id at a time. is there a quicker way of removing semaphores maybe using awk?
Regards,
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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