ZCOM C I/F Library Routines

LTFIND (3X)

LTFIND (3X)

NAME

ltfind – Find specific logical terminal in a group

SYNOPSIS

#include

<zcom/zcomsys.h>

 

#include

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

 

(recommended) */

 

 

int32 ltfind (zap, laddr, llen, ibuf, len)

 

zaddr_type

*zap;

 

char

*laddr;

 

int32

llen;

 

char

*ibuf;

 

int32

len;

DESCRIPTION

Routine ltfind searches through the group linkage in the logical terminal

 

table, for the logical terminal with the specified logical address.

Group linkages are set up by TTGEN to form a circular list of logical terminals that are associated with the same physical terminal table. The linkages and logical addresses are defined using the PTERM and LTERM statements in the TTGEN configuration file.

Typically, these linkages are used in a multiplexing environment: a lower level protocol receives multiplexed messages, which contain ID codes for a higher level protocol to further differentiate the data messages. In such cases, the logical terminals may have unique ID codes as their logical addresses, and ltfind is used to locate a logical terminal ZLU with a specified ID code.

Normally, the logical addresses (maximum of 10-bytes) of a group of logical terminals should be unique within that group.

The libraries libzcom_c.a and libpthread.a must be linked into the calling program by giving the options “-lzcom_c -lpthread” options to cc(1) or ld(1).

Chapter 4

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