From owner-freebsd-stable@FreeBSD.ORG  Thu Sep 30 07:03:34 2010
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Date: Thu, 30 Sep 2010 09:03:33 +0200
From: Ed Schouten <ed@80386.nl>
To: Jeremy Chadwick <freebsd@jdc.parodius.com>
Message-ID: <20100930070333.GU87427@hoeg.nl>
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Cc: freebsd-stable@freebsd.org, ale@FreeBSD.org
Subject: Re: mysqld_safe holding open a pty/tty on FreeBSD (7.x and 8.x)
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Hi Jeremy,

* Jeremy Chadwick <freebsd@jdc.parodius.com> wrote:
> 1) "mysqld_safe > /dev/null 2>&1 &" never released the tty
> 2) "nohup mysqld_safe > /dev/null 2>&1 &" did release the tty

What happens if you run the following command?

	daemon -cf mysqld_safe

The point is that FreeBSD's pts(4) driver only deallocates TTYs when
it's really sure nothing uses it anymore. Even if there is not a single
file descriptor referring to the slave device, it has to wait until
there exist no processes which have the TTY as its controlling TTY.

The `pstat -t' command is quite useful to figure out whether there is
still a session associated with the TTY.

See the following thread:

	http://lists.freebsd.org/pipermail/freebsd-ports/2010-July/062417.html

--=20
 Ed Schouten <ed@80386.nl>
 WWW: http://80386.nl/

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