Installation Exits Involved with Message Processing

MVS™ and JES3 both follow certain criteria to determine where to send a message. You define the criteria when you initialize the MVS system, and later when you initialize the JES3 system. This discussion does not explain everything you need to know about setting up message routing when you initialize MVS and JES3. For complete information about JES3 message processing, see z/OS JES3 Initialization and Tuning Reference.

This topic describes how JES3 handles messages so that you can see how certain installation exits (specifically, exits 57,69, and 70). can be used to further customize message handling in your system, and so that you can choose the correct macro to issue a message in a given situation.