Difference between revisions of "MQOPEN()"
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==Purpose== | ==Purpose== | ||
Open a pointer to a message queue | Open a pointer to a message queue | ||
| Line 9: | Line 8: | ||
==See Also== | ==See Also== | ||
| − | [[MQCLOSE()]], [[MQCREATE()]], [[MQCURMSGS()]], [[ | + | [[MQCLOSE()]], [[MQCREATE()]], [[MQCURMSGS()]], [[MQRECEIVE()]], [[MQSEND()]], [[MQUNLINK()]], [[XML_DECODE()]], [[XML_ENCODE()]], [[XML_GATHER()]], [[XML_SCATTER()]] |
| Line 19: | Line 18: | ||
!<expN>||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(). | + | The MQCLOSE() function is used to close a queue which has been opened with MQOPEN() or MQCREATE(). |
| + | |||
| + | For more examples of handling message queues, please see the examples/mqueue programs in the software distribution. | ||
| Line 37: | Line 38: | ||
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) | |
| − | + | enddo | |
mqclose(mqdes) | mqclose(mqdes) | ||
</code> | </code> | ||
Latest revision as of 10:10, 5 July 2011
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().
For more examples of handling message queues, please see the examples/mqueue programs in the software distribution.
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)
Products
Recital, Recital Server
