TS/MP 2.5 Pathsend and Server Programming Manual

The Pathsend procedures and the ACS subsystem processes do not support the checkpointing of
Guardian interprocess message synchronization IDs. This lack of checkpointing support is an
important consideration when writing fault-tolerant requestor programs that do not use the TMF
subsystem. chapter 3, “Writing Pathsend Requestors” (page 50), provides more information about
writing fault-tolerant Pathsend programs.
The Pathsend procedures allow you to indicate a specific timeout value for each message sent to
a server-class. For example, if you perform SERVERCLASS_SEND_ calls to local and remote systems,
you can specify shorter timeout values for the local sends and longer values for the remote sends.
You can restrict access to Pathway server-classes by Pathsend requestors by having the ACS
subsystem processes perform security authorization checks on each send operation.
The Pathsend procedures and the ACS subsystem processes log error messages in the event of a
processing failure. Your Pathsend requestor can check for these errors and perform recovery actions
Program Structure
The Example 1 (page 38) outlines a Pathsend requestor program written in TAL. This program
handles data entry for the order-processing application introduced at the beginning of this chapter.
NOTE: The program in Example 1 (page 38) illustrates program structure only; it is not a complete
program. For an example of a complete, running Pathsend requestor program, see Appendix B,
“Examples” (page 135).
Designing Requestor Programs 37