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Top Forums Programming POSIX Message Queue Memory Allocation Post 302597322 by sumtata on Friday 10th of February 2012 02:21:45 AM
Old 02-10-2012
POSIX Message Queue Memory Allocation

Hi,

I wanted to know whether the POSIX message queues are statically allocated memory by the kernel based on the parameters specified in the open or as and when we send messages, memory are allocated?

Does the kernel reserve the specified memory for the message queue irrespective of whether the queue is empty or full?
 

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MQ_UNLINK(3)						     Linux Programmer's Manual						      MQ_UNLINK(3)

NAME
mq_unlink - remove a message queue SYNOPSIS
#include <mqueue.h> int mq_unlink(const char *name); Link with -lrt. DESCRIPTION
mq_unlink() removes the specified message queue name. The message queue name is removed immediately. The queue itself is destroyed once any other processes that have the queue open close their descriptors referring to the queue. RETURN VALUE
On success mq_unlink() returns 0; on error, -1 is returned, with errno set to indicate the error. ERRORS
EACCES The caller does not have permission to unlink this message queue. ENAMETOOLONG name was too long. ENOENT There is no message queue with the given name. CONFORMING TO
POSIX.1-2001. SEE ALSO
mq_close(3), mq_getattr(3), mq_notify(3), mq_open(3), mq_receive(3), mq_send(3), mq_overview(7) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2010-08-29 MQ_UNLINK(3)
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