IKJEFT01 – Terminal Monitor Program (TMP)
We can Invoke DB2 subsystem in three ways
2. QMF and
3. IKJEFT01 --- Here we discuss more about this TMP.
IKJEFT1A and IKJEFT1B are not utilities but are rather two alternate entry points for the TSO Terminal Monitor Program initialization routine, IKJEFT01. The DB2 utilities were written to run under TSO, either under a terminal session or in batch.
If you have access to the JCL used to start your TSO sessions, you will see that on the // EXEC statement, PGM=IKJEFT01 most likely (or, in some cases, ADFMDF03, which is a part of TSO/E called the Session Manager which, at shops enlightened enough to run it, calls IKJEFT01 in turn). When running the TMP in batch, in order to have TSO execute a series of TSO commands asynchronously, you can use PGM=IKJEFT01, IKJEFT1A or IKJEFT1B.
The following is taken from the TSO/E User's Guide for z/OS 1.4, section 188.8.131.52.2:
“PGM= “ specifies the module being executed. In addition to IKJEFT01, there are two other entry points available for background execution that provide additional return code and abend support. The differences among the three entry points are:
When a command completes with a non-zero return code, the program goes to the next command. When a command abends, the step ends with a condition code of 12 (X'C').
If a command or program being processed by IKJEFT1A ends with a system abend, IKJEFT1A causes the job step to terminate with a X'04C' system completion code.
IKJEFT1A also returns to the caller the completion code from the command or program in register 15.
If a command or program being processed by IKJEFT1A ends with a user abend, IKJEFT1A saves the completion code in register 15 and then terminates.
If a command, program or REXX exec being processed by IKJEFT1A returns a non-zero return code to IKJEFT1A, IKJEFT1A saves this return code in register 15 and then terminates.
Non-zero return codes to IKJEFT1A from CLISTs will not affect the contents of register 15 and the TMP will continue processing.
For a non-zero return code or an abend from a command or program that was not given control directly by IKJEFT1A, no return code is saved in register 15, and IKJEFT1A does not terminate.
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