The assembler user exit (CEEBXITA), HLL user exit (CEEBINT), and
programmer defaults (CEEUOPT) that are used to initialize the environment
are taken from the first valid entry in the PreInit table. Any occurrences
of CEEBXITA, CEEBINT, and CEEUOPT in other PreInit table entries are
ignored. Unpredictable results will occur if this first entry is deleted
or changed.
If a program in the PreInit table failed to load (return code
8 or 40), the identify_attributes CEEPIPI function can be
used to help determine what table entry address did not resolve.