Re: ptyfs and chroot environments

[christos%astron.com@localhost (Christos Zoulas)]

In article <20100401233702.GA25565%panix.com@localhost>,
Thor Lancelot Simon  <tls%panix.com@localhost> wrote:
>On Thu, Apr 01, 2010 at 11:29:21PM +0000, Christos Zoulas wrote:
>> In article <20100401232440.GA12548%panix.com@localhost>,
>> Thor Lancelot Simon  <tls%panix.com@localhost> wrote:
>> >On Wed, Mar 31, 2010 at 09:58:15PM -0400, Taylor R Campbell wrote:
>> >> (I am not subscribed to this list, so please cc me in replies.)
>> >> 
>> >> ptyfs interacts badly with chroot environments.  Since there can be
>> >> only one ptyfs mount at any given time, a chroot environment cannot
>> >> use ptm(4) to allocate ptys, because it will return /dev/pts/N to the
>> >> userland, which does not (and cannot) exist in the chroot environment.
>> >
>> >I thought /dev/ptmx worked without ptyfs mounted?
>> 
>> It does.
>
>So, why can't the chrooted environment just use that?

Because then you have to pre-create pty devices and you need to be careful
because the same nodes can be used by the non-chrooted ptyfs and you can
run out.

christos