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Date: Mon, 15 Aug 2011 13:38:14 -0700
Message-ID: <CAHu1Y73pODE+hQSWWQsjWCyjV9iq80sYqMOUKoeCMy8FSj3DFw@mail.gmail.com>
From: Michael Sierchio <kudzu@tenebras.com>
To: Yuri <yuri@rawbw.com>
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Cc: FreeBSD Questions <freebsd-questions@freebsd.org>
Subject: Re: Group permissions are broken?
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On Mon, Aug 15, 2011 at 1:06 PM, Yuri <yuri@rawbw.com> wrote:
> User john is a member of both webcamd and vboxusers:
> # grep john /etc/group
> webcamd:*:145:john
> vboxusers:*:920:john
>
> When the file /tmp/my-test is owned by webcamd, user john can touch it ok=
:
> $ ls -l /tmp/my-test ; touch =A0/tmp/my-test
> -rw-rw---- =A01 vboxusers =A0vboxusers =A00 Aug 15 12:54 /tmp/my-test
>
> But when /tmp/my-test is owned by webcamd, user john gets an error:
> $ ls -l /tmp/my-test ; touch =A0/tmp/my-test
> -rw-rw---- =A01 webcamd =A0webcamd =A00 Aug 15 13:02 /tmp/my-test
> touch: /tmp/my-test: Permission denied
>
> Why does this error occur? Two groups seem identical. Just different grou=
p
> ids.

/tmp has the sticky bit set.  man 8 sticky