Date: Sat, 24 Jul 1999 17:17:28 +0900 From: Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp> To: Bruce Evans <bde@zeta.org.au> Cc: tlambert@primenet.com, freebsd-smp@freebsd.org, yokota@zodiac.mech.utsunomiya-u.ac.jp Subject: Re: SMP + XDM = keyboard lockup Message-ID: <199907240817.RAA18855@zodiac.mech.utsunomiya-u.ac.jp> In-Reply-To: Your message of "Sat, 24 Jul 1999 09:59:58 %2B1000." <199907232359.JAA29461@godzilla.zeta.org.au> References: <199907232359.JAA29461@godzilla.zeta.org.au>
next in thread | previous in thread | raw e-mail | index | archive | help
>>2) Why doesn't getty use O_EXCL on the open, such that if
>> it can't get an exclusive lock, it fails? Worst case
>
>Perhaps because O_EXCL has no effect for devices under BSD (its effect
>is implementation-defined except for regular files).
Isn't this O_EXLOCK rather than O_EXCL? (open(2)) In any case, we
don't seem to have exclusive lock for non-regular files. (flock(2))
syscons observes TS_XCLUDE just like tty(4), but it is not useful for
getty and xdm (and the X server) because they are run by root.
TIOCEXCL void
Set exclusive use on the terminal. No further opens are per-
mitted except by root. Of course, this means that programs
that are run by root (or setuid) will not obey the exclusive
setting - which limits the usefulness of this feature.
Kazu
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-smp" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199907240817.RAA18855>