This account contains an article by Mark Hartigan on how he
got DCL to work correctly as a Catch-All for MCR on RSX-11M-Plus
systems. This configuration has many advantages over using TDX
or other configurations, and we have become quickly attatched to
it.

The one factor it doesn't mention is how to keep some of
the TDX commands we like, like CVT (base conversion) and DLG
(Display LoGged in terminals). These are retained by installing
TDX under these task names, such as

INS TDX/TASK=...CVT
INS TDX/TASK=...DLG
INS TDX/TASK=...DLN
INS TDX/TASK=...CHD

once for each retained TDX function. I should point out that
we are running M-Plus with secondary pool and external task
headers, so having these extra tasks installed does not cost
anything in primary pool.

Also note: you should build the DCL catchall as a seperate task
image from the one you will use (if any) for a CLI. Specifically, the
catch all should be built so it DOES NOT pass any unrecognized commands
back to MCR (or you will get a race condition), and SHOULD NOT pass any
commands beginning with a "." back to MCR. The build command files
generated for DCL by SYSGEN are clearly commented to tell you how to do
this: you will probably want to make a copy of them with a new name
(such as DCLCATCH) rather than DCL.