11-11-2010
Quote:
mq_open( "/iothreadNewTest", oflags,(S_IRUSR | S_IWUSR),NULL)
What value are you using for oflags? If this is the first time you are connecting to this queue, you need to pass O_CREAT to tell mq_open to create the queue.
Here is a link to very good documentation on all the mq_ functions (and other POSIX functions), that I found very helpful while implementing a message-queue based solution:
Alphabetical Index - M
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LEARN ABOUT OSF1
mq_unlink
mq_unlink(3) Library Functions Manual mq_unlink(3)
NAME
mq_unlink - Removes a message queue (P1003.1b)
LIBRARY
Realtime Library (librt.so, librt.a)
SYNOPSIS
#include <mqueue.h>
int mq_unlink (
const char *name);
PARAMETERS
*name Specifies a pointer to the pathname of a message queue.
DESCRIPTION
The mq_unlink function removes a message queue named by the pathname. After a successful call to this function, subsequent calls to the
mq_open function fail if they specify the queue identified by the name argument and the O_CREAT flag is not set.
Close the connection to the queue with a call to the mq_close function before calling the mq_unlink function. If one or more processes have
the message queue open when mq_unlink is called, destruction of the queue is postponed until all references to the message queue are
removed. In this situation, the mq_unlink function returns immediately, without waiting for all queue references to be closed.
RETURN VALUES
On successful completion, the function returns the value 0 (zero); otherwise, the function returns the value -1, sets errno to indicate the
error, and the message queue remains.
ERRORS
The mq_unlink function fails under the following conditions:
[EACCES] Permission is denied to unlink the message queue.
[ENAMETOOLONG] The length of the name string exceeds {NAME_MAX} while {_POSIX_NO_TRUNC} is in effect.
[ENOENT] The named message queue does not exist.
Additionally, any error that can be returned by the open or fstat file system calls can be returned by the mq_unlink function.
RELATED INFORMATION
Functions: mq_close(3), mq_open(3)
Guide to Realtime Programming delim off
mq_unlink(3)