Reverse dependencies

[fireboy1919]

I've noticed that none of the portage tools consider reverse dependencies - none consider tools that depend upon a certain package.

This can be a sort of serious issue, especially for low level libraries. For example, let say you install a version of QT each time there's an update, and update or install a few new packages. All of the older packages that depend upon the given library still require the old QT libraries, so you have to have them all - some for the new stuff and some for the old. That's a lot of wasted space (not to mention missing the possible benefit of the newest library).

Since there is no reverse dependency checking, the system will not determine which packages should also be updated along with QT to make the old QT libraries unnecessary (if possible). Therefore, cruft will continuously build up in gentoo systems which live on the edge of development, and the only way to fix it is manually updating every single installed package that needs the library (finding out which ones by hand).

A similar problem arises in unmergeing packages. Recently, I decided to stop using KDE and all KDE programs. I was surpised to learn that when I typed
"emerge unmerge --pretend kde"
the only thing that would have left was KDE, and not all of the things that depend upon kde. I had to manually find all of the packages in my package list and unmerge them all individually.

While we're on the subject of emerge, wouldn't
"emerge --unmerge --pretend kde" make more sense? That is, shouldn't "unmerge" have to dashes before it, indicating that it is an argument?

This is the most useful package management system I've seen. However, this huge feature is one that all of the other mainstream package management systems have which portage doesn't, which is a very bad thing, because this problem probably does more for either lowering system stability or adding cruft (depending on what the owner of the system tries to do to get around the problem) than anything else.

I could be wrong about this. Before I learned all that I have about gentoo, I assumed that every package management system would naturally have this feature, as it seems (to me) to be a natural part of any such system. If I am, I apologize. But even so, this means I don't have a clue how to get portage to check to see what programs depend on a library by specifying the library.

[craftyc]

Why did you post this twice?
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Postcount ++

[fireboy1919]

Browser error, I think. I really did only submit it once.