ZCOM C I/F Library Routines

ZLTMX (3X)

 

ZLTMX (3X)

NAME

zltmx – Control logical terminal multiplexing

SYNOPSIS

#include

<zcom/zcomsys.h>

#include

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

int32 zltmx (zap, mode)

zaddr_type *zap;

int32 mode;

DESCRIPTION

Routine zltmx is used to enable or disable the multiplexing of logical

 

terminals. This routine allows dynamic control of the

 

ZCOM_LTFLAG_OMX and ZCOM_LTFLAG_IMX logical terminal flag

 

bits. These flag bits are initialized for each terminal ZLU by TTGEN, and

 

may be changed by use of this call.

 

After calling this routine, the subsequent zrcvr and zsend calls will work

 

according to the new settings.

 

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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