> At first I was pretty much in favor of the changes Alan was 
> suggesting, but Mike brought out an excellent point.  I 
> realize, or suspect, that IBM Endicott and perhaps a lot of 
> other shops may run with RSCS as the standard userid for the 
> RSCS machine, but in 2 out of the 3 companies for which I 
> have worked in my professional career, we didn't.  

I think we're discussing two things here: 

1) what the default for new installs should be

2) what the logic for listing possibilities and selecting the RSCSid
should be

For #1, I don't see much reason to vary from Alan's proposal. A majority
of the people who are doing new VM installs have no reason (or
sufficient knowledge of how) to change the RSCS userid, and those who
do, can do so without any additional pain that isn't present now.
Implementing Alan's suggested solution breaks nothing that works now,
and fixes things that don't work properly now if the system RSCSid is
not set correctly (LPR (ASYNC and PPS as examples). 

There are lots of historical reasons to change the RSCS id, but none
apply to new installs, and the old methods to do so still work without
change. 

#2 doesn't depend on #1. Yes, it would be nice if the logic worked
differently or permitted different selections, but unless we go back to
telling people how to properly configure SYSTEM NETID as part of the
install, I say the default needs to serve the majority case, and allow
people to change it if they need to, which doesn't *require* any
additional change to the logic. The two are separate and distinct
issues. 

> Changing the system rscs (note small
> letters) id to RSCS is not a trivial task given the tendency 
> to imbed the id in execs.  Leaving the default or undefined 
> as "*" has a lot of merit.  It at least causes an error that 
> is noticeable and can easily be fixed in one place rather 
> than having errors drag out until all of the execs that will 
> be run get used and cause an error.

I guess I don't see how this is any different than any other case of
hard-coding constant values in programs. I see the following
possibilities: 

If 'RSCS','VNET' etc. is hard-coded in an exec and that's not the system
RSCSid, you're going to lose and the default value returned by IDENTIFY
isn't gonna matter in the slightest, because the exec isn't paying any
attention to it in the first place.  Response: fix exec to check output
of IDENTIFY.

If the exec checks the output of IDENTIFY, it should get the correct
RSCSid, unless you forgot to update SYSTEM NETID, and I don't see how
IBM can be expected to read our minds (at least not until the
z9-ICan'tBelieveItsNotAMD with optional Virtual Brain Stems becomes
available) and know that it's supposed to use RSCSVNET instead of the
default. Computer does what we tell it, and a default of '*' or 'RSCS'
are equally wrong in this case. Response: fix SYSTEM NETID.

If you change the system RSCS to some other id, don't update SYSTEM
NETID and leave the default RSCS userid in place, then the spool files
end up in spool for user RSCS, which will generate the same phone call
as having it end up in the user's rdr when what they expected to happen
with the output doesn't happen. No data is lost, and if the user didn't
notice a problem with the output not appearing, they're pretty unlikely
to find the files in their rdr and have any clue what to do with them
there. Response: fix SYSTEM NETID, fix exec to check output of IDENTIFY
if needed. 

If you change the system RSCS to some other id, don't update SYSTEM
NETID, and remove the default RSCS userid (common practice these days to
be required to remove unused system userids as part of policy), then you
get a big bang when someone tries to generate output to RSCS, and it
generates the same phone call with the same response: fix SYSTEM NETID,
fix exec to check output of IDENTIFY if needed. 

I don't see where this is taking away any flexibility that exists now,
and it's a change that doesn't impose a lot of work on IBM to 'just get
it right the first time' for 90 plus percent of modern VM systems. 

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