MQCREATE()

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Purpose

Create a message queue and open a pointer to the queue


Syntax

MQCREATE(<expC> [,<expN>])


See Also

MQCLOSE(), MQCURMSGS(), MQOPEN(), MQRECEIVE(), MQSEND(), MQUNLINK(), XML_DECODE(), XML_ENCODE(), XML_GATHER(), XML_SCATTER()


Description

The MQCREATE() function creates and opens a new message queue. It returns a numeric pointer when the queue is opened successfully, or a -1 if unsuccessful. The <expC> is the name of the queue to create and open. Since the pointer is required to identify an open queue to other messaging functions, always assign the return value to a memory variable. The optional <expN> determines the queue access mode:


<expN> Access Mode
Unspecified Read only access
0 Read only access
1 Write only access
2 Read/Write access


The MQCLOSE() function is used to close a queue which has been opened with MQCREATE() or MQOPEN().

For more examples of handling message queues, please see the examples/mqueue programs in the software distribution.


Example

// Open up the queue for read/write access
mqdes=mqcreate("/myqueue2", 2)
if (mqdes < 0)
    messagebox(strerror()+",errno="+alltrim(str(error())))
    return
endif
// send a message to the queue
rc = mqsend(mqdes, "Test message")
if (rc < 0)
    messagebox(strerror()+",errno="+alltrim(str(error())))
    return
endif
mqclose(mqdes)


Products

Recital, Recital Server