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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LEARN ABOUT LINUX
mq_unlink
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)