Permission settings with 'S' or 's' in execute position

nwef

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Jun 6, 2003, 10:23:13 AM6/6/03

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Can anyone explain the occurence of an 'S' or 's' in the execute
position of the permission string? ie) "-wrxw sw x"
Thanks,
Nancy Wefler

Anne Tuchscherer

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Jun 6, 2003, 11:15:54 AM6/6/03

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This is often referred to as the sticky bit. It used to be used a long
time ago (in UNIX years) for keeping things in memory. Now, if it is on
a directory it will make the group the same for any files created in
that directory (unless changed manually). Not sure what it does on an
executable.

I do know that if the s is capitalized it means that the execute bit in
not set. If you want to remove the s or S you can only remove it by
using chmod g-s <file or dir>. It can be set either by chmod g+s <file
or dir> or chmod 2755 <file or dir>.

Anne Tuchscherer
Medstar Health

Uli Link

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Jun 6, 2003, 12:29:10 PM6/6/03

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> This is often referred to as the sticky bit. It used to be used a long
> time ago (in UNIX years) for keeping things in memory. Now, if it is on
> a directory it will make the group the same for any files created in
> that directory (unless changed manually). Not sure what it does on an
> executable.

If the -s is set for the owner the binary is executed with the context of
the owner,
same for the group. Popular example is "top" which needs some kernel
privileges in is executed with s-bit for the group.

>
> I do know that if the s is capitalized it means that the execute bit in
> not set. If you want to remove the s or S you can only remove it by
> using chmod g-s <file or dir>. It can be set either by chmod g+s <file
> or dir> or chmod 2755 <file or dir>.
>

chmod syntax same as for dirs.

---
Uli

Jurjen Oskam

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Jun 6, 2003, 12:31:58 PM6/6/03

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In article <1e45d342b95219a8...@free.teranews.com>, Anne Tuchscherer wrote:

> This is often referred to as the sticky bit. It used to be used a long
> time ago (in UNIX years) for keeping things in memory. Now, if it is on

You're describing the 't' bit here. The 't' bit is called the sticky bit.
The 's' bit is the setuid- or setgid-bit.

For the original poster: read
http://www.cs.rutgers.edu/~watrous/unix-protections.html, found after a
ten second Google-session.

> I do know that if the s is capitalized it means that the execute bit in
> not set. If you want to remove the s or S you can only remove it by
> using chmod g-s <file or dir>. It can be set either by chmod g+s <file
> or dir> or chmod 2755 <file or dir>.

This is correct.

--
Jurjen Oskam

PGP Key available at http://www.stupendous.org/

Rog

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Jun 6, 2003, 6:38:30 PM6/6/03

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-rwxrwsrwx

GUID - whenever this file is executed, it will run with the same group id as
the owner regardless of the id of the person executing it

-rwsrwxrwx

SUID - whenever this file is executed it will run with the same user id as
the owner, regardless of the id of the person executing it

"nwef" <nwe...@dbs1.com> wrote in message
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Villy Kruse

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Jun 10, 2003, 6:43:29 AM6/10/03

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On Fri, 6 Jun 2003 23:38:30 +0100,
Rog <NON> wrote:

>-rwxrwsrwx
>
>GUID - whenever this file is executed, it will run with the same group id as
>the owner regardless of the id of the person executing it
>
>-rwsrwxrwx
>
>SUID - whenever this file is executed it will run with the same user id as
>the owner, regardless of the id of the person executing it
>

Close, The EFFECTIVE user id is set to the owner of the file. The REAL
user id remains the same as the uid of the invoking process.

Villy

Arie Maat

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Jun 24, 2003, 8:25:40 AM6/24/03

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Hi,

Also an helpfull link:

http://docs.sun.com/db/doc/816-4883/6mb2joasa?a=view

Good luck,

Arie Maat

"nwef" <nwe...@dbs1.com> wrote in message
news:487bb720.03060...@posting.google.com...

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