What is Copybook and Copylib

Mayos · New User Joined: 11 Apr 2005 Posts: 16

Hello,

Just want to know what a copybook is and what is a copylib and when it is used in the jcl.

Many thanks.

superk · Posted: Thu Apr 14, 2005 4:16 pm Post subject: Re: Copybook and Copylib

They aren't. Those are terms relating to COBOL programs.

andycool · Active User Joined: 12 Apr 2005 Posts: 65

Hi Mayos,

1. A COPYBOOK can contain some portion of your COBOL program.
For instance you have two programs: prog1 and prog2.
Both of these use a same set of working storage variables. Here, instead of using them twice in both programs, you can make a COPYBOOK ie another pgm/dataset letz say "progcpy", wch will only contain these working storage variables and nothing else.
This is called a working storage cpybook. You can incluse this "progcpy" in both of your pgms by using the statement:

====prgcpy====
05 working_variable1
05 working_variable2
05 working_variable3
============
prog1
UNEXPANDED: - progcpy

prog2
UNEXPANDED: - progcpy

2. A COPYLIB is the one where, after compiling your programs, the copy of it is picked up by the CICS scrn.

...Regards

Mayos · New User Joined: 11 Apr 2005 Posts: 16

Thank you so very much for your explanation. It is very helpful. I appreciate it. Many thanks.