MQOPEN()
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Revision as of 03:57, 10 April 2017 by Yvonne.milne (Talk | contribs)
Contents
Purpose
Open a handle to a message queue
Syntax
MQOPEN(<expC> [,<expN>])
See Also
JSON_DECODE(), JSON_DECODE_FILE(), JSON_ENCODE(), MQCLOSE(), MQCREATE(), MQCURMSGS(), MQRECEIVE(), MQSEND(), MQSENDMESSAGE(), MQUNLINK(), XML_DECODE(), XML_ENCODE(), XML_GATHER(), XML_SCATTER()
Description
The MQOPEN() function opens an existing message queue. It returns a numeric handle when the queue is opened successfully, or a -1 if unsuccessful. The <expC> is the name of the queue to open. Since the handle is required to identify an open queue to other messaging functions, always assign the return value to a 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 MQOPEN() or MQCREATE().
Example
mqdes=mqopen("/myqueue") if (mqdes < 0) messagebox(strerror()+",errno="+alltrim(str(error()))) return endif do while (mqcurmsgs(mqdes) > 0) mstr=mqreceive(mqdes) if (empty(mstr)) messagebox(strerror()+",errno="+alltrim(str(error()))) return endif messagebox(mstr) enddo mqclose(mqdes)