06-15-2011
I strongly advise you to check the return code by the system calls. That way, you'll catch early error like invalid mq descriptor caused by a failed mq_open.
HTH, Loïc
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LEARN ABOUT HPUX
mq_close
mq_close(2) System Calls Manual mq_close(2)
NAME
mq_close - close a message queue descriptor
SYNOPSIS
DESCRIPTION
The system call removes the association between the message queue descriptor, mqdes, and a message queue. Use of this message queue
descriptor by the process, after a successful return from this and until this descriptor is returned by a subsequent will result in the
failure of message queue system calls, with set to
If the process has a registered notification request with the message queue associated with this mqdes, the registration is canceled and
the queue becomes available for another process to register a notification request.
If the message queue has been unlinked and mqdes is the only existing open descriptor for the queue, the queue is destroyed.
To use this function, link in the realtime library by specifying on the compiler or linker command line.
RETURN VALUE
returns the following values:
Successful completion.
Failure.
is set to indicate the error.
ERRORS
If fails, is set to one of the following values:
mqdes is not a valid message queue descriptor.
is not supported by the implementation.
SEE ALSO
mq_open(2), mq_unlink(2), mq_notify(2).
STANDARDS CONFORMANCE
mq_close(2)