problems while using messaging queues....

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LEARN ABOUT V7

mq_close

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

       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

Linux								    2017-09-15							       MQ_CLOSE(3)

Programming