Related Concepts

You need to understand:

JES2 can issue ENF (event notification facility) signal 40 during initialization or orderly termination to communicate the fact that JES2 has initialized, or is ending.
JES3 issues ENF signal 40 during initialization or when the JES3 address space is ending (regardless of orderly shutdown or abnormal termination).
Issue the Return Job ID call (SSI function code 21) to "disconnect" from JES and return the job ID that was obtained with SSI function code 20.
When JES2 processes the Request Job ID call from a task started under the master subsystem, some of the attributes of this task will be defined by the JOBCLASS(STC) initialization statement. Specifically, the value defined on the MSGCLASS parameter determines if the joblog output produced from the SSI function code 20 job is suppressed. In this example, you must define the MSGCLASS parameter of the JOBCLASS(STC) initialization statement so that the class has a disposition of purge. Note that changing the MSGCLASS value may produce an undesirable effect on other started tasks in your system.