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Date: Tue, 15 Feb 2011 06:12:04 -0800
Message-ID: <AANLkTim3w-qqh8aoucd10JYYo1bn+cwEYyHakUf5Zfc2@mail.gmail.com>
From: Garrett Cooper <yanegomi@gmail.com>
To: John Baldwin <jhb@freebsd.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: [PATCH] fix impossible case with waitpid(2) in truss
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On Tue, Feb 15, 2011 at 4:41 AM, John Baldwin <jhb@freebsd.org> wrote:
> On Monday, February 14, 2011 11:12:02 pm Garrett Cooper wrote:
>> Hi,
>> =A0 =A0 waitpid(2) returns a value in the set { -1, 0, <pid> } (-1 in th=
e
>> event of an ERROR, 0 when WNOHANG is specified, <pid> when the process
>> exits according to wait(2)); it never returns a value < -1.
>> =A0 =A0 If someone could commit this patch it would be appreciated.
>> Thanks,
>> -Garrett
>
> I went with '< 0' to match the style used for ptrace() invocations in oth=
er
> parts of truss. =A0All four calls to waitpid() in truss were broken in th=
is
> fashion.

    Oops. I just spotted the one issue because I was looking for a
reasonable example for how to do ptrace as I needed to clean off some
related cobwebs for $JOB.
Thanks for finding the rest of the issues!
-Garrett