Guardian Application Conversion Guide

Being Opened by and Communicating With a High-PIN Requester
Converting TAL Applications
3–46 096047 Tandem Computers Incorporated
Being Opened by and
Communicating With a
High-PIN Requester
This subsection describes how to convert a TAL server to communicate with a high-
PIN requester. Whether you need to convert the server process depends in part on
whether the server tracks its openers. If the server does keep track of its openers, you
should enable the server to run at a high PIN as described in “Converting a TAL
Program to Run at a High PIN,” earlier in this section, and then convert the server as
described under “Converting a Server,” later in this subsection.
If the server does not track its openers, or if you choose not to perform the conversion,
then you can keep the server process at a low PIN and not convert it, except for setting
the HIGHREQUESTERS object-file attribute as described under “Setting the
HIGHREQUESTERS Attribute to Allow High-PIN Openers,” later in this subsection.
Setting this attribute enables a high-PIN requester to open a low-PIN server.
Converting a Server If your server process tracks its openers, you must convert the following parts of your
program:
Defining an opener table
Opening $RECEIVE
Reading D-series system messages from $RECEIVE
Getting information about system messages
Processing system messages
Replying to a system message
Using the OPENER_LOST_ procedure to maintain an opener table
Figure 3-7 shows the processes involved in converting an application. The steps
described in this subsection apply to the server process $SRV.
Figure 3-7. Converting a TAL Server to Communicate With a High-PIN Requester
$SRV
$REQ
Requester
Process
TAL Server
Process
TACL