In message <20001228133116.A9001@felt.ne.mediaone.net>, Matt Herzog writes:
>If I had a file with the permissions -r-xr-sr-x and
>I screwed up those permissions, what chmod argument
>would I use to get them back? I can't seem to get the 
>-sr- bit set.

-sr- is three bits.  See the man page for chmod.  The 'r' is part of the 'o'
permission set.

's' is like "S and x".  "S" is just set[ug]id.

Thus, you'd want
	2555
555 gets you "-r-xr-xr-x", and then the 2 turns the group 'x' into an 's'.

-s