Patrick, >> so that it would work on either z/OS or VSE.
If that is the underlying problem...Here is how I do it: Develop (use any editor but first version is) on the weaker of the two (in 99.99% VSE). That way you will have solutions for whatever comes up in z/OS. What remains are the "realy close to the iron" problems....those will be done in HLASM anyway where a variable telling the op-sys is no problem. And don't forget to phrase a requirement, where you have the feeling that VSE is really lacking. They (IBM-VSE) claim that they maintain compatibility. -- Martin Pi_cap_CPU - all you ever need around MWLC/SCRT/CMT in z/VSE more at http://www.picapcpu.de