Difference between revisions of "MQOPEN()"
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Yvonnemilne (Talk | contribs) |
Yvonnemilne (Talk | contribs) |
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| Line 37: | Line 37: | ||
mqdes=mqopen("/myqueue") | mqdes=mqopen("/myqueue") | ||
if (mqdes < 0) | if (mqdes < 0) | ||
| − | + | messagebox(strerror()+",errno="+alltrim(str(error()))) | |
| − | + | return | |
endif | endif | ||
do while (mqcurmsgs(mqdes) > 0) | do while (mqcurmsgs(mqdes) > 0) | ||
| − | + | mstr=mqreceive(mqdes) | |
| − | + | if (empty(mstr)) | |
| − | + | messagebox(strerror()+",errno="+alltrim(str(error()))) | |
| − | + | return | |
| − | + | endif | |
| − | + | messagebox(mstr) | |
end do | end do | ||
mqclose(mqdes) | mqclose(mqdes) | ||
Revision as of 10:57, 19 November 2009
Purpose
Open a pointer to a message queue
Syntax
MQOPEN(<expC> [,<expN>])
See Also
MQCLOSE(), MQCREATE(), MQCURMSGS(), MQRECEIVE(), MQSEND()
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().
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) end do mqclose(mqdes)
Products
Recital, Recital Server
