On Fri, 19 Jun 2009 10:27:15 -0500
Troy Dawson wrote:

Hi Troy,

[...]
> > So the question is, who installed ati-fglrx and why...
> > 
> 
> My guess
> puppet
> Why?
> Because puppet can work on generalities.  You can say that you want
> the driver for your video card, and it can figure out the correct
> driver.
Well, these are the packages (related to libGL) that I install with
puppet:
xorg-x11-devel.i386/x86_64
xorg-x11-Mesa-libGL.i386/x86_64
xorg-x11-Mesa-libGLU.i386/x86_4

they provide libGL,  but those packages not explain (for me) why
ati-fglrx is installed.
Maybe, if they're not installed yet, yum solves dependency with
ati-fglrx.
does it make sense to you?


[...]

> > so, I understand that in order to get libGL.so.1 installed yum must
> > install all packages listed in above output. Am I right?
> > 
> 
> No, on this point you are wrong.
> The dependancy is libGL.so.1, and *any* of the "provider" packages
> can supply that package.  It only has to install one of those
> packages.  If your repositories were just plain SL, it would be
> xorg-x11-Mesa-libGL. But since you have (it looks like) sl-contrib
> and dag enabled, it can pick whichever one it feels is right.
Ok, so now some questions about yum algorithm come to my mind:

1.-) Every time that yum has to install a package that needs libGL (for
this example) does it try to install a package that provithes that
library? or it only sees that libGL is already installled and install
the desired package?

2.-) fist time that yum knows that needs libGL, how does it take the
decission on which package from all that provides libGl has to install? 
for example:
host A: package A needs libGl, it installs ati-glrx first and solves
dependency, and later, puppet installs xorg-x11-Mesa-libGL that also
solves the problem. 

host B: package A needs libGL but as xorg-x11-Mesa-libGL is already
installed, it does not need ati-glrx.

am I saying something senseless? 
any link to yum internal?


thanks for your reply Troy.

> Troy
Arnau