"backup" copies to a special filesystem hierarchy all files which have been modified since the previous run of backup on that filesystem. It helps to reduce the number of tape restores by keeping online copies of recently changed files. Backup uses a modified version of GNU find that reads the filesystem i-list, which speeds things up quite a bit, at the expense of portability. The modified find works on sunos4-5 and irix4-5 systems. - ken@cs.toronto.edu