OSI/AS Programming Manual

Example 2: Presentation Layer and ACSE
Sample Programs
056783 Tandem Computers Incorporated E–31
Example 2:
Presentation Layer
and ACSE
This example consists of a requester program and a server program that communicate
with each other to demonstrate the use of the Presentation Layer, ACSE, and basic
concatenation. The programs, as written, both run on the same Tandem system.
The requester does the following:
Issues an ACSE associate request to a remote application, then waits for the
confirm
Sends a presentation data request plus a token give request using basic
concatenation
Waits for a presentation data indication
Waits for an ACSE release indication, then issues the response
The server does the following:
Waits for an ACSE associate indication from a remote application, then issues the
response
Waits for a presentation data indication
Waits for a presentation token give indication
Sends a presentation data request
Requests the release of the connection
To run this example, you must have an OSI/AS subsystem with an OSI manager
process named $OMGR and two applications named APPL1 (the requester) and
APPL2 (the server). The OSI/AS subsystem can be configured to use either session
version 1 or session version 2. Once you have configured the subsystem, run APPL2
first, and then run APPL1.
Requester Program The following pages give the source code for the requester program (Application 1),
which is configured as APPL1.
TAL Version
? INSPECT, SYMBOLS
? NOCODE, NOMAP, NOLMAP
? PAGE "OSI/AS Sample Program 2 (Application 1)"
--
-- File: EXAPST2A
--
-- OSI/AS Sample Program 2 (Application 1)
--
-- General:
-- This is an example ACSE/Presentation program.
-- It illustrates how to call the APS procedures.
-- Some liberties have been taken in error checking;
-- real applications would include error checking.
-- This program calls the APS procedures in wait mode.
--
-- OSI/AS configuration: