Last month, we talked about the basic structure, and some of the general details, of the TSO Broadcast Dataset, which used to exclusively be called SYS1.BRODCAST. The Broadcast Dataset is part of the "messaging facility" which belongs to TSO under MVS, and it has been around (as SYS1.BRODCAST) since the MVT times, long before MVS was given its name.  read more »

TSO has been around, on OS/360 (circa late-1960s) and on later MVT and MVS systems, for many years. Being the "terminal access" mechanism for the Operating System, and being "User and Userid oriented", TSO (in MVS) has always had a messaging system, so that one user could send messages to another user.
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