Re: [Synaptic-devel] Trouble with updating xfree86

[Panu Matilainen]

On Thu, 25 Mar 2004, Andreas Schmidt wrote:

> Hi,
> 
> yesterday I set to work seriously to upgrade xfree86 on my unstable-box  
> from 4.2.1 to 4.3.0. Since it came out, I've been afraid I'd s... up my  
> system because of unresolved dependencies.
> 
> On the command-line,
> address@hidden:/home/pc# apt-get install --dry-run xbase-clients xfonts- 
> 100dpi xfonts-75dpi xfonts-base  xfonts-scalable xfree86-common xfs   
> xfwp xlibs xlibs-dev xnest xserver-common  xserver-xfree86 xspecs xterm  
> xutils  xvfb
> would work OK. However, that's what I only discovered yesterda. Before,  
> when I marked all these packages for update in synaptic, I got warned  
> that an exceedingly huge number of packages (Gnome/GTK-related) would  
> be removed. Marking each of the xfree86-packages individually led to  
> xbase-clients being the single package that caused all that havoc.
> 
> Apparently, the packages marked for removal depended on libice6 or  
> xlibs (>4.1.0); so their dependency was fulfilled by xlibs 4.2.1.  
> xbase-clients (4.3.0) depends on xlibs (4.3.0). Somehow, when marking  
> all xfree86-packages it doesn't seem to get through that the xlibs- 
> dependency still is fulfilled, resulting in the mass-removal.
> 
> Finally, when selecting all packages of the xfree86-packages except  
> xbase-clients, xbase-clients is listed among the packages that will be  
> upgraded and nothing is marked to be removed.
> 
> I'm not sure what is wrong there, but as passing all of the xfree86- 
> related packages to apt-get install works I guess synaptic is behaving  
> a bit...unexpectedly. :-)

This sounds awfully similar to this case where it was found that synaptic 
uses a slightly different algorithm than apt to resolve broken 
dependencies: 
http://mail.gnu.org/archive/html/synaptic-devel/2004-01/msg00065.html

..and indeed there seem to be some subtle differences in the way apt and
synaptic handle resolving installation dependencies... Don't have time to 
dig into that right now but certainly something to check sooner or later.

        - Panu -