On Mon, 5 Jul 2010 09:20:12 -0700, Charles Mills wrote: >Absolutely, a sub-task can and normally does exit via BR 14. One of the >elegances of OS/360 and its descendents (as opposed, for example, to DOS/360 >and its descendants) is that a module can be entered and exit without >knowing or caring whether it was invoked by CALL, LINK, ATTACH, or EXEC >PGM=. > It started out so nicely. Alas, somewhat after, it became necessary for a module to know and care whether it was entered by one of those other mechanisms, or as a Command Processor by the TSO TMP.
Never could figure out what the designers were thinking when they made that choice. And an elegance of YA OS that you didn't mention is that is not necessary for the invoker to know whether the invoked is a machine executable or a script in one of various interpreted languages. Wouldn't it be nice to be able to mix program objects and Rexx EXECs in the same STEPLIB concatenation, and even in the same library? -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
