Difference between revisions of "MQOPEN()"
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The MQCLOSE() function is used to close a queue which has been opened with MQOPEN() or MQCREATE(). | The MQCLOSE() function is used to close a queue which has been opened with MQOPEN() or MQCREATE(). | ||
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==Example== | ==Example== | ||
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[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Functions]] | [[Category:Functions]] | ||
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[[Category:Messaging Functions]] | [[Category:Messaging Functions]] | ||
[[Category:Lianja VFP Extensions]] | [[Category:Lianja VFP Extensions]] | ||
[[Category:VFP Function Extensions]] | [[Category:VFP Function Extensions]] |
Revision as of 07:59, 4 February 2013
Contents
Purpose
Open a pointer to a message queue
Syntax
MQOPEN(<expC> [,<expN>])
See Also
MQCLOSE(), MQCREATE(), MQCURMSGS(), MQRECEIVE(), MQSEND(), MQUNLINK(), XML_DECODE(), XML_ENCODE(), XML_GATHER(), XML_SCATTER()
Description
The MQOPEN() function opens an existing 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 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 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)