BETA News 10-05-21 -- ALPHA Released

[Carlos Aguilera]

Phil:



It is probably a dumb question, could you explain to me/us what exactly are
the function of SHADOW files, I thought their function was to safeguard any
changes from affecting the real ones and they were practically disposable
but your point says otherwise. Am I right? Is there any documentation on the
subject available?





Carlos Aguilera

1401 Liggates Rd

Lynchburg VA 24502

Carlos-FiVMtmHp2a9Wk0Htik3J/***@public.gmane.org

434-401-4828

[herc_fun]

Shadow files can be used to make updates to DASD volumes "disposable", just delete the shadow file and the updates to the base DASD volume disappear. Shadow files can also be used to apply a "permanent" set of changes to the base DASD volume; usually to do this you would mark the shadow file as read-only and Hercules will automatically create an additional new shadow file to hold updates to the volume.

Check out the docs at http://www.hercules-390.org/cckddasd.html

Hope that helps,
Regards, Charlie

Post by Carlos Aguilera
It is probably a dumb question, could you explain to me/us what exactly are
the function of SHADOW files, I thought their function was to safeguard any
changes from affecting the real ones and they were practically disposable
but your point says otherwise. Am I right? Is there any documentation on the
subject available?
Carlos Aguilera
1401 Liggates Rd
Lynchburg VA 24502
434-401-4828

[Mike Stramba]

Post by herc_fun
Shadow files can be used to make updates to DASD volumes "disposable", just
delete the shadow file and the updates to the base DASD volume disappear.

Which in this case, (deleting shadow files) is probably not a good idea ;)

And there needs to be a distinction between deleteing the shadow files
using "external" host commands, versus the Hercules sf- (remove shadow
file) command which by default will MERGE the shadow file into the
original dasd (unless the original dasd's config definitions have the
-ro (read only) option)

The (missing) js3xx, js2xxx shadow file definitions are causing the
errors for OP

I just used the supplied config file (conf /t3upd.conf), which already
has the shadow definitions in it, and I'm sure that's why I didn't get
the errors.