smart query --requires= versus apt-cache rdepends

[Gustavo Niemeyer]

Hello Pascal,

> while trying out the smart package manager, i noticed that the result of the 
> following commands differs on my Ubuntu 8.04 system ("Benötigt" is german for 
> requires):

Yes, the result is different because they don't have the same semantics.
The --requires option of the query subcommand takes the description of
a *provided relation*, not a package name like APT.  It answers the
question: "Supposing that something provides DEPENDENCY, who would
require it?".  This means that it takes version information too: you
can do something like "--requires name=1.0", and this would match if
some package requires "name >= 0.9", for instance.

What you want is also supported by Smart though.  Check it out:

$ smart query --show-provides --show-requiredby smartpm-core
(...)

smartpm-core_0.52-2
   Provides:
     smartpm-core = 0.52-2
       Required By:
         smartpm_0.52-2 (smartpm-core = 0.52-2)
         kpackage-kde4_4:4.0.3-0ubuntu2 (smartpm-core = 0.52-2)
smartpm-core_0.52-hardy1-landscape9
   Provides:
     smartpm-core = 0.52-hardy1-landscape9
       Required By:
         smartpm_0.52-hardy1-landscape9 (smartpm-core = 0.52-hardy1-landscape9)
         landscape-client_1.0.6-hardy1-landscape1 (smartpm-core = 
0.52-hardy1-landscape9)
         kpackage-kde4_4:4.0.3-0ubuntu2 (smartpm-core = 0.52-hardy1-landscape9)

> By the way, it is a little bit confusing, that "--requires=DEP" means the 
> opposite of "--show-requires DEP", or am I missing something?

I think you're missing some details indeed.

--requires takes an argument, and limits the shown packages.

--show-requires *doesn't* take arguments, doesn't restrict the package
selection, and simply makes Smart display some additional information
for the shown packages.

-- 
Gustavo Niemeyer
http://niemeyer.net