On Tuesday 18 December 2007, Mike Miller wrote: > On Tue, 18 Dec 2007, Samir M. Nassar wrote: > > So why can't we use deb or rpm to install these packages? For the most > > part because a gentoo system wouldn't know what you installed. > > I read your whole message but I just have a question about the paragraph > above. What does it mean for Gentoo to "know" what is installed? I'm not > picking on your choice of wording, I'm trying to understand where in the > system that information is recorded and used. I can direct my path > through the right directories (e.g., /usr/local/bin) and I should find > everything, even on Gentoo -- in that sense I know what is there. > Is the problem you refer to that Gentoo's own installer system wouldn't > know that dependencies are already taken care of and it would force me to > reinstall things that are alaredy installed because it doesn't see them? All package management systems keep track of what is installed and what isn't to some degree. They also take care of dependency resolving. This puts the manage in package management. Each package management system has a place where it keeps track of installed packages. The format of this database and the location differs from package management system to package management system. Reinstalling an already installed dependency is problematic if done improperly. So if you installed something critical to your toolchain (glibc, gcc, binutils) with one package management system and then installed other versions you might create a situation that corrupts how your applications compile and how they run. This problem is not confined to Gentoo but will occur in almost any system. One can maintain several copies of software on their system, but more care needs to be taken to isolate them so that conflicts don't happen. Some package management systems will install parallel copies of certain software. Each package management system has its own method of accomplishing that goal. -- Samir M. Nassar samir.nassar at steamedpenguin.com