From owner-freebsd-current@FreeBSD.ORG  Mon Oct 11 13:17:20 2010
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Date: Mon, 11 Oct 2010 15:17:19 +0200
From: Ed Schouten <ed@80386.nl>
To: delphij@FreeBSD.org, current@FreeBSD.org
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Subject: truss calls setpgid()
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Hi all,

I've been seeing this bug for a very long time, but I was too lazy to
figure out the root cause earlier. It is TTY related, but in this case
the TTY layer is not to blame. It does things correctly.

When you run a command in truss which calls ioctls on TTYs, it just
locks up. This is because truss runs jobs in a separate process group.
This also means you cannot send signals to it:

	truss sleep 10000

Pressing ^C here won't work.

I've fixed it locally like this:

Index: usr.bin/truss/setup.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
--- usr.bin/truss/setup.c       (revision 213113)
+++ usr.bin/truss/setup.c       (working copy)
@@ -78,7 +78,6 @@
        }
        if (pid =3D=3D 0) { /* Child */
                ptrace(PT_TRACE_ME, 0, 0, 0);
-               setpgid (0, 0);=20
                execvp(command[0], command);
                err(1, "execvp %s", command[0]);

Question: was this intentional? I'd rather not break stuff.

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

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