Assembler steps are identified by one of these EXECs:

• EXEC PGM=IFOX00
• EXEC PGM=IEUASM
• EXEC PGM=IEV90
• EXEC PGM=ASMBLR
• EXEC PGM=ASMA90
• EXEC ASMS
• EXEC PGM=asmpgm [if the JCLIN specified ASM(PGM=asmpgm)]
• EXEC asmproc [if the JCLIN specified ASM(asmproc)]

Either ASSEM or SRC entries are built, depending on where the assembler input is obtained.

• ASSEM entries are built when the assembler input is inline (the SYSIN DD statement does not point to another data set).
• SRC entries are built when the SYSIN DD statement points to a member of a partitioned data set.