On Tue, 13 Feb 2007 12:34:59 -0800 Andrew Sackville-West <[EMAIL PROTECTED]> wrote:
> On Tue, Feb 13, 2007 at 08:58:05PM +0100, David Jardine wrote: [snip] > > If I understand the meta-package concept right, the meta-package > > depends on the real packages, but nothing depends on the > > meta-package. Removing it would therefore have no side-effects. > > Or have I got it wrong? > > > > On surface I think you're right unless you get into the auto/manual > package tagging in aptitude. > > I'll admit that I don't fully understand it within the context of > aptitude, but AIUI... > > install a package called dep3, it is marked as manually installed and > will be left alone by aptitude. > > install meta1, that meta-package is marked as manually > installed so aptitude will not remove it without explicit > instructions. meta1 depends on dep1, dep2, dep3. dep1 and 2 get > installed and aptitude marks them all as automatically > installed. dep3 is already installed, fine. > > now install meta2 which depends on dep2 and dep4. Now dep2 is already > installed, but not dep4 which gets pulled in and also marked as > automatically installed. > > Now you have: > > meta 1 -manual > dep1 -auto > dep2 -auto > dep3 -manual > > meta 2 -manual > dep2 -auto > dep4 -auto > > So later when you remove meta1, aptitude goes > through all its dependencies and checks to see if anything *else* > depends on them too. It looks at dep1 and sees that nothing else is > depending on it and its marked as automatically installed so marks it > for removal. Next it looks at dep2 and sees that meta2 depends on it > and leaves it. Finally it looks at dep3 and sees nothing depending on > it, but it is marked as manually installed and leaves is alone. > > Likewise, another scenario using the same packages as above: I'm done > with dep3, not realising meta1 depends on it, I remove it. This breaks > meta1, so meta1 gets marked for removal as well cascading to dep1 and > dep2 (which stays because meta2 uses it). > > I don't know how accurate that all is, but that's how I view it and it > seems to keep me out of trouble. > > A So would I be correct in saying that using aptitude is safe, using apt-get is safe, just don't mix the two? Regards -- John K Masters - User #417400 in the Linux Counter http://counter.li.org/ No trees were killed in the creation of this message. However, many electrons were terribly inconvenienced. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
