Chip Davis wrote:
... when shared segments were implemented in VM.
It seems to me that it predated the VM/370 SEPP/BSEPP days when I
started, but there's been many a synapse lost since then.
VM/370 R6 does have DCSS (DisContiguous Shared Segments IIRC) - Even
without SEPP or BSEPP.
But of course, contrary to modern VM systems (ie, VM/XA onward), these
needed to be defined when the nucleus is built (via DMKSNT) - and space
had to be allocated (that is, even though the space was allocated as
"PERM", you had to make sure no user MDISKs were sitting there) and
formatted (through IPL FMT) especially for this purpose on a CP owned DASD.
Note that VM/370 R6 is still being actively used as a learning tool by
some individuals who aren't lucky enough to have access to a modern and
up to date VM system - since it is the last VM release that was
available as a no-charge SCP - and is also believed to be de-jure
(although IANAL) public domain because of the lack of copyright
statement and because it was release prior to the 1976 copyright laws.
--Ivan