HP 9000 Networking XTI Programmer's Guide

API Tracing Using Environment Variables

Enable API Tracing

API tracing for XTI also allows you to control tracing via environment

variables. When using this method, you do not need to write any special

code in your application to take advantage of API tracing.

The following is an example of this mechanism for XTI:

% XTI_TRACE=io; export XTI_TRACE

% active -L foo -N addr -R zzz

Fri Oct 9 10:43:06 1992 - t_open()

name = "/dev/ositpi"

oflag = 0x2

tinfo->addr = 55

tinfo->options = 160

tinfo->tsdu = -1

tinfo->etsdu = 16

tinfo->connect = 32

tinfo->discon = 64

tinfo->servtype = 1

Fri Oct 9 10:43:07 1992 t_open() = 3

t_open: OK

Fri Oct 9 10:43:07 1992 - t_alloc()

fd = 3

fields = 0x1

struct_type = T_BIND

Fri Oct 9 10:43:07 1992 t_alloc() = 0x400038D8

....

This example shows the environment variable, XTI_TRACE, being set to

the ASCII characters "io" (meaning input and output parameters). For

csh(1) users the setenv(1) command should be used. The program is then

invoked and the API tracing is automatically enabled to the level speciﬁed in

the environment variable.

The program shown does not require any special user code for handling the

environment variables, or controlling the API tracing global variables. The

mechanism works by having the XTI library itself test the environment

variables on the ﬁrst valid XTI call (always t_open) and then set the global

API trace variables according to the value of the environment variables. If

no environment variables are present, then no API tracing takes place.