Hi to all,
I'm installing ROOT analysis program on a machine with Fermilab SL v. 
3.0.3 . I cannot install it because the package "X11-devel" is not
installed.

So i tried to install this package using the visual tool "Add/Remove
package" included in distribution. I guess that it is in the "X11
Develepment" package group, but i cannot install it because there are some
missing dependancies that cannot be found (isn't strange that there are
packages without their dependancies?!?!?).

So i looked for the RPMs present in the installation CDs and i found (in
the 2nd CD):

XFree86-devel-4.3.0-68.EL.i386.rpm

The problem is that the installed X11 version is 4.3.0-81, i.e. it is
newer that the one on the installation CDs (and also using command line
"rpm" fails because of missing dependances or newer versions), so i guess
that there a sort of "automatic update tool" on the distribution.

I discovered that this tool is "yum", in fact there is always a cron
process running it.

In the How To of the SL site, i found instructions about using this "yum",
but i cannot execute on a shell "yum" because there is already another
"running yum" in background.

How can i add this "X11-devel" package and all its required dependances?
Consider that i'm not the pc owner, so all i do must be safe.

I thank you in advance

Matteo Alfonsi