MQ_CLOSE(3) Linux Programmer's Manual MQ_CLOSE(3)NAME
mq_close - close a message queue descriptor
SYNOPSIS
#include <mqueue.h>
int mq_close(mqd_t mqdes);
Link with -lrt.
DESCRIPTION
mq_close() closes the message queue descriptor mqdes.
If the calling process has attached a notification request (see (mq_notify(3)) to this message queue via mqdes, then this request is
removed, and another process can now attach a notification request.
RETURN VALUE
On success mq_close() returns 0; on error, -1 is returned, with errno set to indicate the error.
ERRORS
EBADF The message queue descriptor specified in mqdes is invalid.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+-----------+---------------+---------+
|Interface | Attribute | Value |
+-----------+---------------+---------+
|mq_close() | Thread safety | MT-Safe |
+-----------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
NOTES
All open message queues are automatically closed on process termination, or upon execve(2).
SEE ALSO mq_getattr(3), mq_notify(3), mq_open(3), mq_receive(3), mq_send(3), mq_unlink(3), mq_overview(7)COLOPHON
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Linux 2017-09-15 MQ_CLOSE(3)
Check Out this Related Man Page
mq_close(3RT) Realtime Library Functions mq_close(3RT)NAME
mq_close - close a message queue
SYNOPSIS
cc [ flag... ] file... -lrt [ library... ]
#include <mqueue.h>
int mq_close(mqd_t mqdes);
DESCRIPTION
The mq_close() function removes the association between the message queue descriptor, mqdes, and its message queue. The results of using
this message queue descriptor after successful return from this mq_close(), and until the return of this message queue descriptor from a
subsequent mq_open(3RT), are undefined.
If the process (or thread) has successfully attached a notification request to the message queue via this mqdes, this attachment is removed
and the message queue is available for another process to attach for notification.
RETURN VALUES
Upon successful completion, mq_close() returns 0; otherwise, the function returns -1 and sets errno to indicate the error condition.
ERRORS
The mq_close() function will fail if:
EBADF The mqdes argument is an invalid message queue descriptor.
ENOSYS The mq_open() function is not supported by the system.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
SEE ALSO mqueue.h(3HEAD), mq_notify(3RT), mq_open(3RT), mq_unlink(3RT), attributes(5), standards(5)NOTES
Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned
-1 and set errno to ENOSYS.
SunOS 5.10 28 Jun 2002 mq_close(3RT)
Hello,
J have a problem when I use gcc:
This comand works:
gcc -shared -fpic -I/usr/include/sys -I/usr/include -L/usr/lib/librt.sl essai1.c mylib.sl
but
gcc I/usr/include/sys -I/usr/include -L/usr/lib/librt.sl essai2.c -o essai
don't work.
The first command creates a dynamique... (1 Reply)
hi
I am using posix functions such as mq_open, mq_close and including the mqueue.h. but its giving a linking error,"undefined reference to mq_open and mq_close".
it it that we have to link some library or so while compiling... plzzz help
Thanxs
Mohit (0 Replies)
Hi guys.
i have wrote a simple program to test message queue attributes. here it is:
#include <stdio.h>
#include <stdlib.h>
#include <mqueue.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <sys/stat.h>
int main()
{
struct mq_attr attr;
mqd_t mqd;
... (2 Replies)
Hi All,
First of all thanks for reading this post.
In my application, I am trying to create a new message queue . I am attaching the code below.
mqd_t mqopen2(const char * pName,
unsigned long Flags,
long maxMsg,
long msgSz)
{... (15 Replies)
hello, I try to test the POSIX mq_open function on book unp like below:
#include "unpipc.h"
# include <mqueue.h>
int main(int argc, char **argv)
{
int c, flags;
mqd_t mqd;
flags = O_RDWR | O_CREAT;
while ((c = getopt(argc, argv, "e")) != -1) {
... (3 Replies)