On Mon, 30 Oct 2017 23:13:33 +1300 Richard Hector <rich...@walnut.gen.nz> wrote:
> On 30/10/17 15:46, Celejar wrote: > > On Sun, 29 Oct 2017 08:28:46 -0400 > > The Wanderer <wande...@fastmail.fm> wrote: > > > >> On 2017-10-29 at 07:49, Jörg-Volker Peetz wrote: > >> > >>> Celejar wrote on 10/24/17 15:09: > >>> > >>>> On Tue, 24 Oct 2017 08:52:46 +0200 > >>>> Jörg-Volker Peetz <jvpe...@web.de> wrote: > >>>> > >>>>> I forgot that you showed the dependency on cups-filters in your > >>>>> original mail. > >>>>> On testing cups-filters 1.17.9-1 does not depend on imagemagick, it only > >>>>> recommends it. And I use APT::Install-Recommends "false"; in > >>>>> /etc/apt/apt.conf. > >>>>> Therefore, on this system imagemagick could be removed. > >>>> > >>>> Interesting, thanks. So they changed the dependency from 'depends' to > >>>> 'recommends', but they're still 'recommending' a dummy package. > >>> > >>> Taking another look at package imagemagick-6.q16 (version > >>> 8:6.9.7.4+dfsg-16) it > >>> states that it provides imagemagick. Therefore, I don't understand what's > >>> going > >>> on on your system and there's nothing wrong with package cups-filters, I > >>> think. > >> > >> My guess involves vague memories of there being an issue with versioned > >> Provides: - although I thought that was more "you can't Provides: a > >> specific version", not "a versioned Depends: won't be satisfied by a > >> Provides: from a package with a suitable version number". > > > > I don't understand this stuff well enough to add anything to the > > conversation. All I know is that I still can't remove imagemagick > > despite the fact that imagemagick-6.q16 "Provides:" imagemagick. > > > > Celejar > > > > imagemagick-6.q16 Provides: imagemagick, but not a specific version > > cups-filters Depends: imagemagick (>= 6.4~) > > The real imagemagick package is at 8:6.9.7.4+dfsg-11+deb9u1 (on my > machine anyway), which satisifies the cups-filters dependency. > > The system doesn't know whether the version of imagemagick Provided by > imagemagick-6.q16 is new enough, so you still need the real package. Ah, thank you. I couldn't find the whole Depends: / Provides: rules clearly documented anywhere, but that certainly explains it. So either imagemagick-6.q16 should be more specific about which version of imagemagick it "Provides:", or, if that's not possible (as per Wanderer's suggestion), then cups-filter needs the 'imagemagick' package, and it's not quite a dummy that can be removed. > Richard Celejar
