[mod.computers.vax] What's the *story* here?!

hobbit@AIM.RUTGERS.EDU.UUCP (03/28/87)

VMS upgrades involving image patching usually patch an extant image in the
system tree, write a new image in the "kit working directory" and then
copy that over to the tree, superseding the original image.

If Patch finds an ECO level already set when the .VUP file tries to set it,
the replacements performed under that ECO level aren't written when Patch
finds an UPDATE command.

There are several files in the 4.5 VMS update that already have ECO levels
set and from what I can see already have the fixes provided by the 4.5 .VUP
file.  So why is the .VUP file there?  A short example is LOGINOUT, which
has ECO level 1 already set from the 4.4 mandatory.  No new image is written
at all, since no changes are done under anything but ECO level 1, so your
"provide_file" or equivalent *fails*.

What's going on?  Did someone completely lose track of what versions of things
were being shipped/updated?  Should I simply go ahead and use the extant images
for those cases that weren't updated, or should I mung around with the ECO
levels?  What did other people who upgraded from 4.4 to 4.5 do with this?

_H*
------

carl@CITHEX.CALTECH.EDU.UUCP (03/29/87)

 > There are several files in the 4.5 VMS update that already have ECO levels
 > set and from what I can see already have the fixes provided by the 4.5 .VUP
 > file.  So why is the .VUP file there?  A short example is LOGINOUT, which
 > has ECO level 1 already set from the 4.4 mandatory.  No new image is written
 > at all, since no changes are done under anything but ECO level 1, so your
 > "provide_file" or equivalent *fails*.
 >
 > What's going on?  Did someone completely lose track of what versions of things
 > were being shipped/updated?  Should I simply go ahead and use the extant images
 > for those cases that weren't updated, or should I mung around with the ECO
 > levels?  What did other people who upgraded from 4.4 to 4.5 do with this?

Consider the following question:  would you rather have an  upgrade  warn  you
that no change was made to a file because it had already been patched, or have
it fail  to  make  a  required  patch  because  it  assumed  that  a  previous
installation  had already made it?  I think you'll agree that the former is by
far the preferable option.  VMSINSTAL  is  probably  one  of  the  least  well
documented  VMS  utilities  extant, and one of the things you apparently don't
know about it is the fact that it's frequently possible to get it to install a
product  on a system that is running too low a version of VMS for that product
to be guaranteed to work properly (one use for this  feature  is  to  let  you
install  layered  products  before  applying  the  mandatory  update  to a VMS
upgrade.  For example, the 4.4 mandatory update patched several DECnet images,
but normally you wouldn't have installed DECnet (on a uVMS system) until after
the mandatory update, so you'd have to run  the  update  again  to  patch  the
DECnet  files).   Thus,  it's  necessary  for  upgrade  procedures  to be very
conservative in their assumptions  regarding  the  ECO  levels  of  the  files
they're dealing with.  The only thing the 4.5 upgrade could be reasonably sure
of was that the files were at least at the ECO level of the  4.4  distribution
BEFORE  THE  MANDATORY  UPDATE  (since  4.4 gave you a completely new suite of
system files).  Thus, the 4.5 kit included VMSMUP 4.4 in order to  be  certain
you  got  all the patches you needed.  So, in answer to your question, use the
images as the 4.5 upgrade left them.  It knew what it was doing.