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Date: Thu, 10 Jul 2003 16:21:50 -0400 (EDT)
From: Matthew Emmerton <matt@compar.com>
To: Terry Lambert <tlambert2@mindspring.com>
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cc: freebsd-hackers@freebsd.org
Subject: Re: RFC: Change to sys_errlist
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On Sun, 6 Jul 2003, Terry Lambert wrote:

> Matthew Emmerton wrote:
> > This is a RFC on a change to sys_errlist for errno = 0.
> >
> > On Linux, if perror() or strerror() is called with errno = 0, the resulting
> > string is "Success".
> > On FreeBSD, the resulting string is "Unknown error: 0".
> >
> > I think that FreeBSD's output is unintentionally confusing, as errno = 0
> > implies success.
> >
> > The following patch will change the output to the Linux behaviour.
> >
> > I appreciate any comments.
>
> Actually, I ran into a situation on MacOS X the other day that had
> a system call with a -1 return code with an errno == 0.
>
> I would personally like to distinguish this case, if only for the
> purpose of catching kernel errors.  Saying "Success" when in fact
> the system call is returning -1 is a bogus thing to do.

Agreed.  I thought this over and read some specs and believe our way is
the right way.

--
Matthew Emmerton
Computer Partners
IT Specialist