On Thu, 18 Jul 2019 16:54:40 -0400, Thomas David Rivers wrote: > >There is some mumbling in the CMS OS SIMULATION doc that says it allows >the opening of non-existing files for INPUT because CMS can't mimic an empty >(but existing) file vs. a non-existing file. > The ANSI C standard does not require implementations to distinguish between empty files and non-existing files. Presumably because some file systems (e.g. MDFS) don't support empty files. SFS suppports empty files so grudgingly that XEDIT warns the user and requires confirmation to create an empty file.
The ANSI C standard cautions that reading a file may return more trailing blanks than were written, or fewer. RECFM=F is an offender, and neither MDFS nor SFS permits empty lines, so the sequence "\n\n" may either generate a padding blank or elide the empty line. CMS is a moron. -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
