Reference Guide

ZCOM C I/F Library Routines
LTQDGET (3X)
Chapter 4 153
PAR AMETER S
NOTES Normally, the data queue number used should be allocated by ZMON
(see the zltqueue man page for how to get a data queue number). There is
no queue ownership validation within this routine; it is up to the user to
make sure that the queue usage is valid and consistent.
RETURN VALUE Routine ltqdget returns 0 if successful. Otherwise, a non-zero error code
is returned. See /opt/acc/include/zcom/zcomsys.h for the list of ZCOM
error codes and their meanings.
If the specified queue is empty, then the ZENODATA error (-24) is
returned and ibuf contains invalid data.
EXAMPLE
#include <zcom/zcomsys.h>
#include <zcom/zcomcall.h>
int32 ierr;
zaddr_type zaddr;
uint32 queue;
char ibuf[size]; /*Where size is user-determined; must be
>= len */
int32 len;
int32 rlen;
if (ierr = ltqdget (&zaddr, queue, ibuf, len, &rlen)) {
zap ZCOM address of a terminal from which to get
the data.
queue Terminal data queue number (specifies which
data queue is to be used).
0 - Sub-packet holding queue (reserved)
1 - Data holding queue A
2 - Data holding queue B
3 - Data holding queue C
4 - Data holding queue D
ibuf (Return Param) On a successful return, the data is placed into
this buffer.
len Length in bytes of ibuf.
rlenp (Return
Param)
Actual number of bytes returned in ibuf.