SNAX/HLS Application Programming Manual

7 Customization
104707 Tandem Computers Incorporated 7–1
In certain specialized applications, you might wish to intervene in the normal flow of
traffic on a session; for example, you might have to edit data or accumulate and report
performance statistics. SNAX/HLS provides the ability to customize the product by
allowing installation-written routines to be invoked at certain critical processing
points. These routines are sometimes called user-exit routines.
With the present version, an installation can provide routines that SNAX/HLS can
invoke at various points. In effect, this allows user-exit routines to intervene in the
normal processing of SNAX/HLS.
Table 7-1 lists seven user-exit routine names, the purpose for invoking each routine,
and the functions each routine might perform.
Table 7-1. User-Exit Routines and Their Functions
Routine Invocation and Function
SNAXHLS^USEREXIT^ENABLE Invoked by SNAX/HLS at startup. This routine allocates and
presets working storage and tells SNAX/HLS which of the
other customization routines are to be involved during
SNAX/HLS processing.
SNAXHLS^USEREXIT^VERB^OUT Invoked when SNAX/HLS has just accepted a verb request
from the application program. This allows the customization
routine to inspect and perhaps modify the verb request before
SNAX/HLS processes it.
SNAXHLS^USEREXIT^VERB^IN Invoked when SNAX/HLS is about to pass a verb reply to the
application program. This allows the customization routine to
inspect and perhaps modify the verb reply before SNAX/HLS
passes it to the application program.
SNAXHLS^USEREXIT^SNAX^IN Invoked when SNAX/HLS has just received input from the
Tandem SNA access method SNAX/XF. This allows the
customization routine to inspect and perhaps modify this input
before SNAX/HLS processes it.
SNAXHLS^USEREXIT^VRFY^BIND^
RSP
Invoked when SNAX/HLS has just finished processing the
BIND request and is about to send a positive response. This
allows the customization to inspect the BIND request, and
perhaps reject it with user supplied SNA sense data.
SNAXHLS^USEREXIT^VRFY^STSN
^RSP
Invoked when SNAX/HLS has just finished processing the
STSN request and is about to send a positive response. This
allows the customization routine to inspect the STSN request
and modify the response before SNAX/HLS sends it to the
Tandem SNA access method. For example SNAX/XF.