Re: [patch] strcpy.3: Avoid redundantly filling the position 'n - 1' two times in strncpy() example code

Michael Kerrisk
2008-09-25T08:14:08Z

Hi Andre,

On Wed, Sep 24, 2008 at 4:01 PM, André Goddard Rosa
<andre.goddard-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> From 88a02845c606413444bfb055935303b4896d0271 Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?Andr=C3=A9=20Goddard=20Rosa?= <andre.goddard-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Date: Wed, 24 Sep 2008 10:25:08 -0300
> Subject: [PATCH] Avoid redundantly filling the position 'n - 1' two times in strncpy() example code.
> MIME-Version: 1.0
> Content-Type: text/plain; charset=utf-8
> Content-Transfer-Encoding: 8bit
>
> When we use 'strncpy(buf, str, n)', strncpy() will fill chars from 0..(n - 1).
> As we force the character at position 'n - 1' to be '\0' anyway, don't fill it in strncpy() before.

Thanks! Applied for 3.11.

Cheers,

Michael

> Signed-off-by: André Goddard Rosa <andre.goddard-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
> man3/strcpy.3 | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/man3/strcpy.3 b/man3/strcpy.3
> index 7a8091f..d2e08a3 100644
> --- a/man3/strcpy.3
> +++ b/man3/strcpy.3
> @@ -115,7 +115,7 @@ as follows:
> .in +4n
> .nf
>
> -strncpy(buf, str, n);
> +strncpy(buf, str, n \- 1);
> if (n > 0)
> buf[n \- 1]= \(aq\\0\(aq;
> .fi
> --
> 1.6.0.2.508.g24593
>
>
>

--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html
Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html