Re: [PATCH v2 2/2] stpncpy.3, string.3, string_copying.7: Clarify that st[rp]ncpy() pad with null bytes

Alejandro Colomar
2023-11-10T17:46:51Z

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On Thu, Nov 09, 2023 at 11:47:34PM -0600, Oskari Pirhonen wrote:
> On Thu, Nov 09, 2023 at 16:20:39 +0100, Alejandro Colomar wrote:
> > The previous wording could be interpreted as if the nulls were already
> > in place. Clarify that it's this function which pads with null bytes.
> >
> > Also, it copies "characters" from the src string. That's a bit more
> > specific than copying "bytes", and makes it clearer that the terminating
> > null byte in src is not part of the copy.
> >
> > Suggested-by: Jonny Grant <jg@jguk.org>
> > Cc: DJ Delorie <dj@redhat.com>
> > Cc: Jonny Grant <jg@jguk.org>
> > Cc: Matthew House <mattlloydhouse@gmail.com>
> > Cc: Oskari Pirhonen <xxc3ncoredxx@gmail.com>
> > Cc: Thorsten Kukuk <kukuk@suse.com>
> > Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
> > Cc: Zack Weinberg <zack@owlfolio.org>
> > Cc: "G. Branden Robinson" <g.branden.robinson@gmail.com>
> > Cc: Carlos O'Donell <carlos@redhat.com>
> > Cc: Paul Eggert <eggert@cs.ucla.edu>
> > Cc: Xi Ruoyao <xry111@xry111.site>
> > Signed-off-by: Alejandro Colomar <alx@kernel.org>
> > ---
> > man3/stpncpy.3 | 10 ++++++----
> > man3/string.3 | 11 ++---------
> > man7/string_copying.7 | 3 ++-
> > 3 files changed, 10 insertions(+), 14 deletions(-)
> >
>
> ... snip ...
>
> > diff --git a/man3/string.3 b/man3/string.3
> > index aba5efd2b..bd8b342a6 100644
> > --- a/man3/string.3
> > +++ b/man3/string.3
> > @@ -179,21 +179,14 @@ .SH SYNOPSIS
> > .I n
> > bytes to
> > .IR dest .
> > -.SS Obsolete functions
>
> If you're removing this section ...
>
> > .TP
> > .nf
> > .BI "char *strncpy(char " dest "[restrict ." n "], \
> > const char " src "[restrict ." n ],
> > .BI " size_t " n );
> > .fi
> > -Copy at most
> > -.I n
> > -bytes from string
> > -.I src
> > -to
> > -.IR dest ,
> > -returning a pointer to the start of
> > -.IR dest .
> > +Fill a fixed‐width buffer with characters from a string
> > +and pad with null bytes.
>
> ... shouldn't you also move the rest of this up to keep it alphabetized?

Hi Oskari,

Sure! I was trying to find a pattern in the order, but didn't see it
yesterday. Thanks! :)

Cheers,
Alex

>
> - Oskari

--
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