For example:
wget https://releases.ubuntu.com/20.04/ubuntu-20.04.2-live-server-amd64.iso.torrent
# note: not all versions of docker support mounting individual files!
docker run \
--rm \
--volume "$(pwd)/input_/ubuntu-20.04.2-live-server-amd64.iso.torrent:/input/a.torrent" \
btshowmetainfo/btshowmetainfogives
btshowmetainfo 20130326 - decode BitTorrent metainfo files
metainfo file.: a.torrent
info hash.....: 126f82fb33119d2acf93a16cfba6eb1c5787a59f
file name.....: ubuntu-20.04.2-live-server-amd64.iso
file size.....: 1215168512 (4635 * 262144 + 131072)
announce url..: https://torrent.ubuntu.com/announce
announce-list.: https://torrent.ubuntu.com/announce|https://ipv6.torrent.ubuntu.com/announce
comment.......: Ubuntu CD releases.ubuntu.com
curl --silent https://releases.ubuntu.com/20.04/ubuntu-20.04.2-live-server-amd64.iso.torrent | ./btshowmetainfo -
./btshowmetainfo ubuntu-18.04.4-desktop-amd64.iso.torrentClone the repo, then
./build-and-testdocker build . -t btshowmetainfo
# note: not all versions of docker support mounting individual files!
docker pull btshowmetainfo/btshowmetainfo
docker run --rm -v "$(pwd)/input_/ubuntu-18.04.4-desktop-amd64.iso.torrent:/input/a.torrent" btshowmetainfo/btshowmetainfo