Today I discovered app-arch/cfv in the Gentoo tree. In addition to all the usual md5, sha1, etc formats, install the net-p2p/bittornado package (gtk use flag not required) and this utility can also handle hash checking against .torrent files, without the overhead of launching a full blown torrent client and then having to make sure said client can find all the files.
This is useful to me as I torrent on a remote server and download the files over SFTP/FTPS. Very occasionally something can go awry and I have the desire to hash check the files to see if it was an error with the original or something in my copy that perhaps occurred during transit.
With cfv, I can instead simply store the .torrent file alongside the files and then, when I want to check the files, run “
cfv -f foo.torrent“