"all" is tricky, there isn't a standard command on all computers to list the contents of a file, let alone edit. But even my WRT54G has vi installed on it, and

"all" is tricky, there isn't a standard command on all computers to list the contents of a file, let alone edit. But even my WRT54G has vi installed on it, and you can expect to find emacs and vim on almost any *nix.