Seems you have an older version of the tar command, I use, GNU tar version 1.11.2.. the -z option is to decompress (gunzip) automaticly.., you can use the command: gzip -dc cc65-UNIX.tgz | tar -xvvf - or: gzip -d cc65-UNIX.tgz tar -xvvf cc65-UNIX.tar One of these should work.., unless you don't have 'gzip' :-(