ZCOM C I/F Library Routines

ZLTQUEUE (3X)

 

 

ZLTQUEUE (3X)

NAME

 

zltqueue – Logical data queue allocation

SYNOPSIS

 

 

#include

<zcom/zcomsys.h>

 

#include

<zcom/zcomcall.h> /* if compliled with ANSI C (recommended) */

int32

zltqueue (appln, label, queuep)

uint32

appln;

 

 

char

*label;

 

 

uint32

*queuep;

 

 

DESCRIPTION

Routine zltqueue requests a data queue in the logical terminal tables for

 

 

terminals of a specific application number. There is currently a

 

 

maximum of 4 queues. Each queue is identified by the terminal

 

 

application group and a user-defined label. The returned queue number

 

 

(on successful completion) could then be used in subsequent data storing

 

 

and retrieval calls (ltqdput and ltqdget).

 

 

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

 

 

program by giving the options “-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.

 

 

async-signal unsafe

It cannot be called from a signal handler.

 

 

fork unsafe

It cannot be called by a child process after fork(2)

 

 

 

but before exec(2).

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Chapter 4