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In order to research what caused the installation of a given package, I'd like to get a list of packages which depend on that package. I couldn't find anything obvious in man dpkg.

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marked as duplicate by bodhi.zazen, hbdgaf, Eric Carvalho, Eliah Kagan, Tim Aug 12 '14 at 7:47

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

    
Related: askubuntu.com/questions/13296/… – Seth Feb 26 '15 at 3:58
up vote 72 down vote accepted

apt-cache rdepends packagename should do what you want

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1  
Excellent! apt-cache rdepends tofrodos confirmed the suspicion that it was installed by another package (the obsoleted dos2unix). – l0b0 Apr 30 '12 at 13:12
    
Good deal. I do wish there was a recursive option. Sadly there is not as far as I am aware. – hbdgaf Apr 30 '12 at 13:27
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As for today (apt version 0.9.9.1), there is --recurse option that works with rdepends. – jarno Dec 22 '13 at 14:00
    
Thanks for the heads up. /me is even more pleased than he was. – hbdgaf Dec 22 '13 at 22:50
5  
If you add --installed, the output is even useful for packages which can be used by many others: apt-cache rdepends --installed packagename – quazgar May 27 '14 at 22:08

aptitude has a fairly nice way of handling this:

$ aptitude why bash
i   foomatic-filters PreDepends bash (>= 2.05)

It only lists one reason, but that's usually enough...

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2  
Seems like it considers only the installed packages, not everything available. And that was what I needed. – Tuukka Mustonen Jul 25 '13 at 10:06
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For that you want reverse-depends in ubuntu-dev-tools – tumbleweed Jul 25 '13 at 11:38
    
How about debian? – Tuukka Mustonen Jul 25 '13 at 12:08
1  
ubuntu-dev-tools is in Debian – tumbleweed Jul 26 '13 at 11:18

There are more than one way, with each method showing a different output.

For a detailed view of the dependency tree; aptitude install apt-rdepends apt-rdepends bash

Alternatively;

apt-cache showpkg bash

Or a concise list:

apt-cache rdepends bash

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apt-cache showpkg <pkgname> 

Example:

apt-cache showpkg lightdm
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