Mainframe, MVS and zOS Discussion

Hi,

I was asked in an interview "whats the difference between Return code and Condition Code"? I thought I knew it but I got confused with tese two, can you please help me with an explanation and when is what applicable? Appreciate any reply on this.

Thanks.

A return code is passed from a called program back to the calling program. This can occur between two programs within a language or from the program to the operating system. A condition code only exists with JCL and represents a return code passed from the program to the operating system.

That means Return-codes do not have a meaning away from programs?

Precisely -- without a program, how can you have a return code?

The utility IDCAMS somewhat muddies the water, though, as the command response code is referred to as a condition code. It is a return code from the command, though.

Return code is the value in R15 when you return control to your caller.

Cond code (as in JCL) is the value in R15 (0 < cc < 4096) when your program terminates and returns control to z/OS.