From owner-freebsd-hackers@FreeBSD.ORG  Wed Mar 10 20:04:11 2010
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Date: Wed, 10 Mar 2010 21:04:10 +0100
From: Ed Schouten <ed@80386.nl>
To: Alfred Perlstein <alfred@freebsd.org>
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Cc: FreeBSD Hackers <hackers@freebsd.org>
Subject: Re: tty or script(1) weirdness?
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* Ed Schouten <ed@80386.nl> wrote:
> Hmmm... It seems this is a TTY bug. When you close a TTY, the final
> close() call should get stuck until all data is actually drained. This
> doesn't seem to happen properly.

Some further research: it's not a TTY bug, but a bug in script(1).
The script parent process leaves a file descriptor open, which means
output is never properly drained.

I can't reproduce this issue after applying this patch:

%%%
Index: script.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
--- script.c	(revision 204965)
+++ script.c	(working copy)
@@ -158,6 +158,8 @@
 	}
 	if (child =3D=3D 0)
 		doshell(argv);
+	else
+		close(slave);
=20
 	if (flushtime > 0)
 		tvp =3D &tv;
%%%

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

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