hmmm... a strange permission level

[loft306]

so im messing around i changed the permissions on /usr/bin/fcrontab and borked it all up!!!!!
so i need to change it back to

• ---s--s--- 1 cron cron 39540 Apr 24 2004 /usr/bin/fcrontab

however i have never seen this permission level so i don't know how to create it.

[sarumont]

That's the setuid bit. It allows the file to elevate the users permissions to superuser. In your case, it allows the group to do this as well (which is the setguid bit).

chmod 6000 whatever

Will acheive the mode that is on the file in your post. The first bit in that chmod is comprised of 4 for suid and 2 for setgid (the value of 1 is for the sticky bit...rarely used). When you specify only a three bit octal number to chmod, leading zeroes are assumed.

[scientica]

cool you got a setuid and setguid file, with zero permissions - meaning in effect only root can do anything with it... (you could say the permission to be this sentance: "every thing is foridden for this file, and every thing you do (which really is nothing :P) is done as cron (user and group) - only root almighty can change this")

My recomendation, as root, use "chmod" and the power of root
(btw, you really don't want to 'chmod 6000 µsr/bin/fcrontab' (yes that will setguid and setuid it and remove all other options) -- it'll leave the file use less to everyone but root...)


btw, it seems the permission octet is:
Xugo
for X: 1 = sticky, 2 = set guid, 4 = set uid (or any "binary or" of them)
for [ugo] = 1 = exec, 2 = write, 4 = read (or any "binary or" of them)

[edit]bummer.. saramount beat me... I'm to slow writing detailed answers :P[/edit]

[loft306]

Ha ah scientica....i did expect the ansawer from your however
thnx sarumont...
ok so what if i set it 6775 would that give users use of it along with root?

[loft306]

yep! that worked

not to mention the users that need cron are in cron group so are thoes perms apropriate?

[mesut]

Thanks!

(i am using cron on loft306's server )