Re: [PATCH v2] who --mesg now checks the group of TTY devices

[Kamil Dudka]

On Saturday 23 of January 2010 02:43:39 Kamil Dudka wrote:
> On Saturday 23 of January 2010 00:54:44 Kamil Dudka wrote:
> > # ls -l /dev/tty?
> > crw--w----. 1 root root 4, 0 2010-01-22 18:48 /dev/tty0
> > crw--w----. 1 root root 4, 1 2010-01-22 18:48 /dev/tty1
> > crw--w----. 1 root tty  4, 2 2010-01-22 18:50 /dev/tty2
> > crw-------. 1 root root 4, 3 2010-01-22 18:48 /dev/tty3
> > crw-------. 1 root root 4, 4 2010-01-22 18:48 /dev/tty4
> > crw-------. 1 root root 4, 5 2010-01-22 18:48 /dev/tty5
> > crw-------. 1 root root 4, 6 2010-01-22 18:48 /dev/tty6
> > crw--w----. 1 root tty  4, 7 2010-01-22 18:48 /dev/tty7
> > crw--w----. 1 root tty  4, 8 2010-01-22 18:48 /dev/tty8
> > crw--w----. 1 root tty  4, 9 2010-01-22 18:48 /dev/tty9
>
> The listing above is in fact a bit misleading since the group is changed
> to "tty" within login.c from util-linux-ng.

Note that util-linux-ng is not the only package providing login.

Other systems may use e.g. shadow.  Then the TTY group can be set 
in /etc/login.defs.  Look at the TTYGROUP option here:

http://vmlinux.org/cgi-bin/dwww?type=runman&location=login.defs/5

> Kamil