GNU gengetopt The md5sum files are computed on the archives, so that you can check that the archives are intact after downloading. Moreover they are digitally signed by me (Lorenzo Bettini ) with GNU gpg (http://www.gnupg.org). My GPG public key can be found at my home page: http://w3.newnet.it/bettini http://infostud.dsi.unifi.it/~bettini