Re: pty attr race/issue

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

In article <20080307204015.GA4678%antioche.eu.org@localhost>,
Manuel Bouyer  <bouyer%antioche.eu.org@localhost> wrote:
>On Fri, Mar 07, 2008 at 07:38:26PM +0000, Christos Zoulas wrote:
>> Why does xenconsole need to open the slave pty? Can't xenconsoled just
>> open it, set it up the way it wants, then exec xenconsole with fd 0, 1, 2
>> as the slave pty?
>
>Err, no it's not the way it works. You can exec xenconsole later if you
>want, you don't have to start the console when starting the domU (it wouldn't
>be convenient for domains started from /etc/rc.d/xendomains)

File a PR about this then. I understand what is going on and why it is working
under linux (see the Linux comment in tty_ptm.c). Basically linux grants the
slave at openpt, and their grantpt is a no-op. Our grantpt does effectively
a revoke which closes all references to the slave. Next time the slave is
opened, TS_ISOPEN is not set and the tty gets reset to the original settings.
We could add a special flag for the pty case to not do the reset.

christos