Difference between revisions of "MQCREATE()"

Revision as of 11:29, 19 November 2009

Purpose

Create a message queue and open a pointer to the queue

Syntax

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

See Also

MQCLOSE(), MQCURMSGS(), MQOPEN(), MQRECEIVE(), MQSEND()

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:

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