Hello Dear PerlMonks, I've signed integers which a must save in a file in the most compact format because, latter, I must read those values back to retrieve those signed integers... I know that I can use pack and unpack using C4 as format, but in this case I increase the storage space by 25% ! My signed integer values fit perfectly in only 24 bits. Do you have any simple or difficult or perlmonked solution because I was unable to find it ? Do you think that converting my signed integers to unsigned (thus all positive values) integers (because I know what will be the greatest negative integer) can help ? Thanks in advance for your help (or prayers otherwise) ! Germain