On Sep 2, 2010, at 06:39, Scott McLeod wrote: > > You're spot on with LABEL=(,,,IN), an obscure JCL option known mostly to > FORTRAN programmers, and a sure way to make a DD input-only. > > Also years ago, I earned my stripes with our senior MVS systems programmer, > when he was debugging an abend with a vendor's OCO FORTRAN program. The JCL > said DISP=SHR, the operators took the write ring off the tape, yet still the > step abended (because FORTRAN was opening the dataset INOUT). > > Fresh from a couple years working in a research company that used FORTRAN, I > suggested LABEL=(,,,IN), and voila, I earned a friend for life. > Sigh. And a programmer might code DISP=SHR to avoid ENQ conflicts with other volumes even while intending to write to the data set. Perfectly safe with tape.
-- gil
