Does anbody know what the s bit does in unix permissions?

Posted on 2006-04-07
Last Modified: 2010-04-21
This is just a For My Knowledge question. I see permissions in our unix environment that are set to :


I have found that the s stands for set user.

What does that mean?

Question by:scuzz1
    LVL 51

    Accepted Solution

    man chmod

    the s-bit for groups on files changes the the group from the caller's group to the group assigned to the file when it is executed.

    Author Comment


    A couple of us was wondering and we could not find any text on it. Nothing very definitive. I know how to set it but never knew what it actually did.

    LVL 51

    Expert Comment

    keep in mind that the s.bit for directories behaves different (for obvious reason:)

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