Fix a botched package on Arch Linux

fix-arch-botched-updates.md

Sometimes a failed update (due to an unexpected power outage or similar) on Arch Linux may lead to a botched package that is difficult to reinstall due to errors of this type:

perl: /usr/bin/core_perl/corelist exists in filesystem
perl: /usr/bin/core_perl/cpan exists in filesystem

Since pacman no longer has a force option, here is how to fix this:

1. Trying to update the affected package will list all conflicting files - save them to a file:

    sudo pacman -S perl 2>perl-errors.txt
   

2. Extract the filenames:

    awk '{print $2}' perl-errors.txt > perl-filelist.txt
   

3. Delete the conflicting files:

    for f in $(cat perl-filelist.txt) ; do sudo rm "$f" ; done
   

You can now reinstall the package.