ZCOM C I/F Library Routines

LTQDPUT (3X)

 

LTQDPUT (3X)

 

NAME

ltqdput – Store data buffer in terminal data queue

SYNOPSIS

#include <zcom/zcomsys.h>

 

#include <zcom/zcomcall.h> /* if compiled with ANSI C (recommended)

 

*/

 

 

 

int32 ltqdput (zap, queue, ibuf, len)

 

zaddr_type

*zap;

 

 

uint32

queue;

 

 

char

*ibuf;

 

 

int32

len;

 

DESCRIPTION

Routine ltqdput stores a data message in the data queue of the logical

 

terminal tables. It links the message to the end of the specified queue.

 

Retrieval occurs on a First-In-First-Out basis. See the man page for

 

ltqdget on how to retrieve a message in the data queue.

 

The data queue is designed to store a relatively large or unpredictable

 

amount of terminal data in 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

 

during data update and retrieval. In addition, access is restricted to a

 

FIFO order.

 

 

 

The libraries libzcom_c.a and libpthread.a must be linked into the calling

 

program by giving the options “-lzx25 -lzcom_c -lpthread” to cc(1) or ld(1).

Threads

This routine may be called from a multi-threaded application using the

Considerations

POSIX (1003.1c) kernel threads API package. This routine has the

 

following characteristics when called by a multi-threaded application:

 

cancellation point

Thread cancellation can occur when a thread

 

 

 

calls this routine.

async-cancel unsafe The calling thread’s cancelability type must be PTHREAD_CANCEL_DEFERRED if cancellation is enabled.

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