dnf whatprovides and library files

[Gordon Messmer]

On 06/10/2015 12:24 AM, Ed Greshko wrote:
> But, just to be clear, the issue I'm addressing is what an average
> user may do in a given circumstance.  Upon seeing an error message
> such as this one,
>
> error while loading shared libraries: /lib64/libexempi.so.3: file too
> short
>
> assuming they know of dnf whatprovides I think it is more likely they
> will simply use copy/paste and issue the command "dnf whatprovides
> /lib64/libexempi.so.3"

Interesting.  I've never actually seen an error with an installed shared 
object, so I never considered that you'd query one with "whatprovides."

In that case, I agree with you.  rpm and dnf behave differently with 
such a query (which I also did not know):

$ rpm -q  --whatprovides /lib64/libXv.so.1.*
libXv-1.0.10-2.fc22.x86_64
$ dnf whatprovides /lib64/libXv.so.1.*
Error: No Matches found

dnf really should behave the same way as rpm.  If possible, it should 
call the rpm library functions for the query, rather than 
re-implementing them.

> Yes, rpm can tell you this *if* the file and providing package exists
> on your system.  But, it is usual that you get a message about
> something missing and that is where you need dnf.

Yes, but in the case where something is missing, you won't get a path. 
You'll get a shared object name, and querying that with "dnf 
whatprovides" will work correctly, as it is.