My understanding of software dependencies is that a program package may require other packages to be installed, termed dependencies. A tree-like result ensues. Sometimes packages share common dependencies, but the package only needs to be installed once.
|Package D | Package B --------->| | |Package E Package A ------->| | |Package F | Package C --------->| |Package B
I recently posted a question on AskUbuntu.com about finding the dependencies of a package, and all the ways of doing this gave me different results. The reason for this was that some of the methods were apparently listing more than just dependencies, some were performing recursive checks, and some were performing reverse checks.
What is the difference between a reverse dependency check, and a recursive dependency check?
Citations for terms. I first heard them in the comments of a thread I posted about APT, but they are used in several programs that can be used to do dependency checks as well as on their manpages.
apt-cache rdepends is looking for Reverse dependencies, my script and apt-rdepends are recursively looking for dependencies.
rdepends pkg(s) rdepends shows a listing of each reverse dependency a package has.
apt-rdepends - performs recursive dependency listings similar to apt-cache