APAR SYSMOD: Fixing problems with an element

You may sometimes find it is necessary to correct a serious problem that occurs on your system before a PTF is ready for distribution. In this situation, IBM® supplies you with an authorized program analysis report (APAR). An APAR is a fix designed to quickly correct a specific area of an element or replace an element in error. You install an APAR SYSMOD to implement a fix, thereby updating the incorrect element.

In Figure 1, the shaded section shows an area of MOD2 containing an error.

Figure 1. Fixing problems with an element

The processing of the APAR SYSMOD provides a modification for object module MOD2. During the installation of the APAR SYSMOD, MOD2 is updated (and corrected) in load module LMOD2.

Figure 2 shows an example of a simple APAR SYSMOD.

Figure 2. Example of a simple APAR SYSMOD

++APAR(APAR001)             /* SYSMOD type and identifier.   */.
++VER(Z038) FMID(FUN0001)   /* Apply to this product         */
            PRE(UZ00004)    /* at this service level.        */.
++ZAP(MOD2)                 /* Update this module            */
            DISTLIB(AOSFB)  /* in this distribution library. */.
...
... zap control statements
...

The APAR SYSMOD always has the installation of a function SYSMOD as a prerequisite, and can also be dependent upon the installation of other PTF or APAR SYSMODs.

PTF, APAR, and USERMOD SYSMODs all have the function SYSMOD as a prerequisite. In addition to their dependencies on the function SYSMOD:

PTF SYSMODs might be dependent upon other PTF SYSMODs.
APAR SYSMODs might be dependent upon PTF SYSMODs and other APAR SYSMODs.
USERMOD SYSMODs might be dependent upon PTF SYSMODs, APAR SYSMODs, and other USERMOD SYSMODs.

Sometimes a PTF or even an APAR is dependent upon other PTF SYSMODs called corequisites. Consider the complexity of these dependencies– When you multiply that complexity by hundreds of load modules in dozens of libraries, the need for a tool like SMP/E becomes apparent.