[pca] --stop option in pca

[Martin Paul]

Dave,

> Does anyone know of an easy way to stop before a patch?  I ask as the
> pca I have (the one just before today's new release) behaves where it
> applies the patch and then stops.

Yes, I remember that I discussed with Chris Reece (who proposed adding 
the stop option) and we came to the conclusion that stopping *after* a 
patch makes more sense, while the opposite isn't necessary. You just 
proved us wrong :)

Of course this could be handled by a new option, but I'm hesitating to 
add one, as there are so many already. I don't want to change the 
default neither, although with "stop before" the "stop after" could be 
simulated by running "pca --stop ID --install; pca --install ID". It 
would still break default behaviour, which I don't like.

> The problem is, when a kernel
> patch is seen it fails if the zones are up.  Pca continues on applying
> patches, which I don't want it to do as so many of them fail since the
> kernel patch wasn't installed.  I'd like to tell it to stop just before
> the kernel patch so I can halt the zones, apply the kernel patch, then
> start the zones in single user mode again until next kernel patch.

Hm, if the kernel patch fails to install anyway, you could use the stop 
option as-is. You will just have on useless attempt to install the patch.

A cleaner solution might be to run e.g.:

   pca --format '%p-%c # %y' --noheader > plist.txt

Then cut the plist.txt into separate patch groups, split by kernel 
patch(es), and feed it back into pca:

   pca --install plist-1.txt
   halt zones
   pca --install <kernelpatch>
   start zones
   pca --install plist-2.txt
   ...

Hope that helps,

Martin.