In preparing a backup script for my server, I wanted to tar a directory, e.g., tar czvf mydir.tar.gz /path-to-mydir/ and compare it with the "last" versions e.g., last/mydir.tar.gz Even when no changes made, if I do cmp mydir.tar.gz last/mydir.tar.gz I get mydir.tar.gz last/mydir.tar.gz differ: byte 5, line 1 This doesn't happen with zip, so I have a "sort of" workaround. However, I'm curious to the origin of the issue if anyone has ideas. Cheers, JN