Date: Tue, 13 May 2014 17:15:50 -0700 From: Adrian Chadd <adrian@freebsd.org> To: "Mikhail T." <mi+thun@aldan.algebra.com> Cc: Current FreeBSD <freebsd-current@freebsd.org> Subject: Re: Locking console with Ctrl-S hangs various processes (ttydcd) Message-ID: <CAJ-Vmon0v02_m0JRkjx9HdEh=YiyZNBQsFU-MZ5n-smzGvUu2w@mail.gmail.com> In-Reply-To: <53729FBC.5060204@aldan.algebra.com> References: <53729FBC.5060204@aldan.algebra.com>
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Hi! This sounds rather silly and should be fixed. Yes, hanging the vty shouldn't hang the console device. Would you / your friend mind filing a PR? Thanks! -a On 13 May 2014 15:42, Mikhail T. <mi+thun@aldan.algebra.com> wrote: > Hello! > > A fellow FreeBSD user was recently confounded by a problem: various processes on > his 10.0 system were hanging or otherwise misbehaving: su, certain daemons, syslogd. > > They were all hung in the "ttydcd"-state. Searching > <https://www.google.com/search?q=FreeBSD+ttydcd>; for that revealed only, that > other people have seen the problem, but nobody (including the entire > freebsd-stable@ on 2012 > <http://lists.freebsd.org/pipermail/freebsd-stable/2012-June/068281.html>) was > able to offer a solution. > > Apparently, the problem stems from the ttyv0 (which moonlights as /dev/console > for the vast majority of installs) being locked -- such as by pressing Ctrl-S. > One needs not be a root to do it... > > After that, any attempts to write to /dev/console -- which even syslog(3) often > does -- would hang the calling process until the tty is unlocked (such as with > Ctrl-Q). > > This may be the desired behavior for "normal" ttys, but, perhaps, /dev/console > should act differently? > > -mi > > _______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"
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