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Top Forums Programming message queues and multi-process Post 302133154 by rvan on Wednesday 22nd of August 2007 07:23:59 AM
Old 08-22-2007
message queues and multi-process

Hi,

Am supposed to use message queues to send and receive messages between the processes. when i was working on that i realised that the message qid and the message queue related data should be maintained in a shared memory so that it can be accessed by all the processes. Could anybody refer some link which helps me out in this...


P.S. i have gone through Richard Stevens IPC volume 2 but i couldn't exactly find such a scenario..Stevens more on memory mapped I/O..


Thanks,
 

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ipcrm(1)						    BSD General Commands Manual 						  ipcrm(1)

NAME
ipcrm -- remove the specified message queues, semaphore sets, and shared memory segments SYNOPSIS
ipcrm [-M shmkey] [-m shmid] [-Q msgkey] [-q msqid] [-S semkey] [-s semid] ... DESCRIPTION
Ipcrm removes the specified message queues, semaphores and shared memory segments. These System V IPC objects can be specified by their cre- ation id or any associated key. The following options are used to specify which IPC objects will be removed. Any number and combination of these options can be used: -M shmkey Mark the shared memory segment associated with key shmkey for removal. This marked segment will be destroyed after the last detach. -m shmid Mark the shared memory segment associated with id shmid for removal. This marked segment will be destroyed after the last detach. -Q msgkey Remove the message queue associated with key msgkey from the system. -q msqid Remove the message queue associated with the id msqid from the system. -S semkey Remove the semaphore set associated with key semkey from the system. -s semid Removes the semaphore set associated with id semid from the system. The identifiers and keys associated with these System V IPC objects can be determined by using ipcs(1) SEE ALSO
ipcs(1) BSD
August 8, 1994 BSD
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