Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've seen various Linux file permissions such as rwx and rws, but I have never seen the permission set rwS. Can someone please explain to me what the capitol 'S' stands for?

share|improve this question
up vote 10 down vote accepted

The capital S indicates the file has a setuid bit set but is not executable.

[root@host:/]$ touch file
[root@host:/]$ chmod 4755 file
[root@host:/]$ ls -l file
-rwsr-xr-x 1 root root 0 Jul 25 15:05 file
[root@host:/]$ chmod -x file
[root@host:/]$ ls -l file
-rwSr--r-- 1 root root 0 Jul 25 15:05 file
share|improve this answer

From info ls "What information is listed":

    `S'
          If the set-user-ID or set-group-ID bit is set but the
          corresponding executable bit is not set.
share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.