ILBOFLW

ILBOFLW is a COBOL library routine that traces the program statement path of an executing program. This trace information can be used to debug an abend if one occurs during program execution.

Hints

CPU execution in the ILBOFLW subroutine occurs on behalf of a COBOL program when that program is compiled with the FLOW compiler option specified. The trace data generated is useful when you are testing a program. Programs that have been thoroughly tested and are stable, generally do not need this trace information. Recompiling a COBOL program without specifying the FLOW compiler option, or with the NOFLOW compiler option specified, prevents the trace data from being taken and thus removes execution in the ILBOFLW subroutine.

Reference Sources

IBM OS/VS COBOL Subroutine Library Program Logic, LY28-6425.

IBM OS/VS COBOL Compiler Program Logic, LY28-6486.