Jim Henderson wrote:
> Yes, but the information for RPM is stored in a database - or rather a 
> series of databases - implemented using Berkeley DB (on my system, 
> version 8).

I guess if all the information you need to make that decision is stored 
in a transactional database, yah, you should be able to do that sort of 
thing. But then you wouldn't need a read-only version.

The problem with ACID is too many people stop too soon, thinking (for 
example) that "Consistent" means if the internal structure of the 
database storage isn't screwed up means that the database is consistent.

If you upgrade GCC from 2.3 to 2.4, and the /usr/bin/gcc file gets 
rewritten and then you crash out before committing the package manager, 
or you have permissions to write to libgcc and overwrite it but fail to 
upgrade /usr/bin/gcc properly, you have an inconsistency.

Out of curiousity, how do the package managers work when the packages 
are distributed over the network? If /usr/bin is a NFS mount, for 
example, does package management still work? Or are you back to 
tiptoeing around trying to figure out every file a package will touch? 
Can clients upgrade things, or do you have to try to lock it down at the 
NFS server?

-- 
Darren New / San Diego, CA, USA (PST)

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