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Re: pty attr race/issue

In article <>,
Manuel Bouyer  <> wrote:
>On Fri, Mar 07, 2008 at 10:10:05PM +0000, Christos Zoulas wrote:
>> In article <>,
>> Manuel Bouyer  <> 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.
>Do we really want to change this in the kernel ? fvdl@ pointed me to a 
>workaround in xenconsoled, which also works for netbsd-4 ...

Let's just leave it as it is for now.


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