Reverse/backward dependency checking in Slackware
by xj25vm from LinuxQuestions.org on (#5G2CK)
I think I might have asked this question here many years ago - but looking through all my previous posts, I just can't find it. I'm perfectly happy to sort out dependencies when I install a new package in Slackware - the current system works fine: either read the info at SBo, or try to run the software on the command line and it will complain with some relevant error message.
However, I am faced with kind of the opposite problem. I need to start with a package, and find out what depends on it. For example, I have 'twolame' installed - and I was trying to figure out which software installed on the laptop needs it - if any - so that I know if it is safe to remove it. I can't figure out a way to do this. I think someone suggested grep'ing some directory. Going through /var/log/packages/ doesn't seem to help - as the README or package.info files with dependencies info are not stored there. Is there another way to obtain this information? I looked through the Slackware docs and wiki - but all the info seems to be about forward dependency checking - not backwards.
As a small side note, I suppose it would be helpful if SBo would have the option to search through package descriptions on the website - if that is possible at all. This way it would be possible to search for packages which depend on the particular package you are looking at - and then check if any of them are installed on the local machine.


However, I am faced with kind of the opposite problem. I need to start with a package, and find out what depends on it. For example, I have 'twolame' installed - and I was trying to figure out which software installed on the laptop needs it - if any - so that I know if it is safe to remove it. I can't figure out a way to do this. I think someone suggested grep'ing some directory. Going through /var/log/packages/ doesn't seem to help - as the README or package.info files with dependencies info are not stored there. Is there another way to obtain this information? I looked through the Slackware docs and wiki - but all the info seems to be about forward dependency checking - not backwards.
As a small side note, I suppose it would be helpful if SBo would have the option to search through package descriptions on the website - if that is possible at all. This way it would be possible to search for packages which depend on the particular package you are looking at - and then check if any of them are installed on the local machine.