ZCOM C I/F Library Routines
LTQDGET (3X)
LTQDGET (3X)
NAME | ltqdget – Retrieve data buffer in terminal data queue | ||
SYNOPSIS | #include | <zcom/zcomsys.h> | |
| #include | <zcom/zcomcall.h> /* if compiled with ANSI C | |
| (recommended) */ |
| |
| int32 ltqdget (zap, queue, ibuf, len, rlenp) | ||
| zaddr_type | *zap; |
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| uint32 | queue; |
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| char | *ibuf; |
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| int32 | len; |
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| int32 | *rlenp; |
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DESCRIPTION | Routine ltqdget retrieves the data message stored in the data queue of | ||
| the logical terminal tables. It returns the first message in the specified | ||
| queue and releases the buffers back to the ZCOM subsystem free data | ||
| buffer pool. See the man page for ltqdput on how to store a message in | ||
| the data queue. |
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| The data queue is designed to store a relatively large or unpredictable | ||
| amount of terminal data in a FIFO order. When compared to logical data | ||
| storage (refer to zltstore and zltup), the data queues allow terminal data | ||
| to be stored dynamically, that is, memory is used only when data is | ||
| stored. However, it is penalized by incurring more processing overhead in | ||
| data update and retrieval. In addition, access is restricted to a FIFO | ||
| order. |
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| The libraries libzcom_c.a and libpthread.a must be linked into the calling | ||
| program by giving the options | ||
Threads | This routine may be called from a | ||
Considerations | POSIX (1003.1c) kernel threads API package. This routine has the | ||
| following characteristics when called by a | ||
| cancellation point | Thread cancellation can occur when a thread | |
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| calls this routine. |
Chapter 4 | 151 |