Share your knowledge at the LQ Wiki.
Go Back > Forums > Linux Forums > Linux - Newbie
User Name
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!


  Search this Thread
Old 06-08-2005, 04:10 AM   #1
Registered: Apr 2005
Posts: 37

Rep: Reputation: 15
Permission setting


I am familiar with permission format such as x, w, r, but never come across permission s. What is this permission for and what is the value for it if I would like to add the permission using chmod?

Old 06-08-2005, 04:23 AM   #2
Registered: Oct 2004
Location: Belgium
Distribution: Slackware 13.37
Posts: 512

Rep: Reputation: 31
Old 06-08-2005, 04:44 AM   #3
Registered: Jan 2005
Posts: 55

Rep: Reputation: 15
Hi Friend

There are 10 parts of permissions

- - - - - - - - - -
r w x r w x r w x

First single part for file or direcoty , if "-" then file , if "d" then directory

- - - Owner's Permission
r w x

- - - Owner's group Permission
r w x

- - - Other's Permission
r w x

If you want to set a permission on a file

You can like this

chmod -rw- rwx r-x janz

Now janz file has following permissions

Owner has r/w [ Read , Write ]Permission

Owner's group has r/w/x [ Read , Write , Execute] Permissions

and others have r/x [ Read , Execute ] Permissions

Ohh i m fed up from typing.

if you found this article useful then reply me.


Old 06-08-2005, 07:35 PM   #4
Registered: Apr 2005
Posts: 37

Original Poster
Rep: Reputation: 15

Thanks for the reply. But, I'm still not clear on what s or S is for and how to set them. For example, it's mentioned that If SUID is set, then "x" in the owner permissions is replaced to "s", if owner has execute permissions, or to "S" otherwise.
-rws------ both owner execute and SUID are set
-r-S------ SUID is set, but owner execute is not set

Then, what s or S actually does and how to set s or S?
Old 06-08-2005, 09:06 PM   #5
Senior Member
Registered: May 2004
Location: In the DC 'burbs
Distribution: Arch, Scientific Linux, Debian, Ubuntu
Posts: 4,290

Rep: Reputation: 378Reputation: 378Reputation: 378Reputation: 378
The setuid bit causes an executable to be run with the permission of the executable's owner, not the permission of the person executing it. it is used to allow a non priviliged user to run a priviliged command such as passwd, which must manipulate the password database. The setgid bit does the same, but for groups. The capital S means that the setuid/setgid bit is set, but not the underlying executable permission (this is extremely rare). A look at man chmod will tell you how to set/unset these bits.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
SUID and setting 'other' permission to _ _ x hpladd Linux - Newbie 3 06-17-2005 01:37 PM
Setting permission on hard drive petero Linux - Hardware 1 06-03-2005 01:19 AM
Default ttyS1 permission setting gilester Mandriva 8 03-07-2005 01:43 PM
setting up permission dramous Linux - Software 1 10-19-2004 11:44 AM
Permission setting in RH9 Linux - Newbie 2 01-21-2004 01:12 PM > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 12:09 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration