patches (was Re: linux security)

[Jeff Silverman]

On Thu, 23 Jan 2003, Jesse Keating wrote:

> On Wednesday 22 January 2003 22:22, Ethan Merritt uttered:
> > Actually in the most comon case, of wanting backwards compatible
> > shared libraries, it works just fine.  Say you have libfoo-1.0.1 installed,
> > and you want to install version 1.0.2 without breaking programs that
> > explicitly linked to libfoo-1.0.1.  You can just install the new version,
> > leaving both /usr/lib/libfoo.so.1.0.1 and /usr/lib/libfoo.so.1.0.2 in
> > place. By convention on distros I am familiar with (mostly Mandrake), the
> > files subject to being overwritten are maintained in a separate and
> > parallel rpm called libfoo-devel-1.0.2.  Installing or upgrading that one
> > would create the symlinks
> >   libfoo.so.1.0 -> libfoo.so.1.0.2
> >   libfoo.so.1 -> libfoo.so.1.0
> >   libfoo.so -> libfoo.so.1
> 
> Yes, that is correct.  Red Hat also maintains different packages for different 
> versions of libraries.  You can have two different versions of openssl 
> installed (as long as the actual library files changed) to satisfy different 
> apps that are looking for the older version of openssl.  But a rpm rebuild 
> (where they patched somethign in the current build, or fixed something in the 
> spec) and the lib versions will be the same, must be -Uvh'd, to replace the 
> old with the new.
> 
> 
Forgive me if I'm a little slow: the first coca-cola of the morning hasn't 
quite kicked in yet.

For a long time, I have either installed or upgraded software on RPMs 
using the 

rpm -Uvh PACKAGE-new_version

command.  If I understand what you are telling me, I should use the 

rpm -ivh PACKAGE-new_version

command, and then when I am ready to get rid of the old version, use

rpm -evh PACKAGE-old_version

to get rid of the old version? 

But, if I am installing a patch or a minor update to an existing package, 
then go ahead and use

rpm -Uvh PACKAGE-new_version

I guess I am asking for a more detailed policy of when to use -i and when 
to use -U


Many thanks,


Jeff


-- 
Jeff Silverman, 
Senior Computing Specialist 3, Fire and Environmental Research Applications (FERA) team.
jeffs at duet.cfr.washington.edu   (206) 732-7815
http://duet.cfr.washington.edu