From: Andreas Schwab <schwab@suse.de>
To: Florian Weimer <fweimer@redhat.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [review] manual: Clarify strnlen, wcsnlen, strndup null termination behavior
Date: Wed, 30 Oct 2019 11:00:00 -0000 [thread overview]
Message-ID: <mvm8sp2h51r.fsf@suse.de> (raw)
In-Reply-To: <87a79i33kt.fsf@oldenburg2.str.redhat.com> (Florian Weimer's message of "Wed, 30 Oct 2019 11:55:30 +0100")
On Okt 30 2019, Florian Weimer wrote:
> * Andreas Schwab:
>
>> On Okt 30 2019, Florian Weimer (Code Review) wrote:
>>
>>> +Note that @var{s} must be an array of at least @var{maxlen} bytes. It
>>> +is undefined to call @code{strnlen} on a shorter array, even if it is
>>> +known that the shorter array contains a null terminator.
>>
>> This is not true. strnlen _always_ stops before the null byte.
>
> This is not how it is specified in POSIX.
Yes, it is.
The strnlen() function shall return the number of bytes preceding
the first null byte in the array to which s points, if s contains a
null byte within the first maxlen bytes; otherwise, it shall return
maxlen.
There is nothing undefined here. Your interpretation would be
completely useless anyway.
Andreas.
--
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."
next prev parent reply other threads:[~2019-10-30 11:00 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-30 10:25 Florian Weimer (Code Review)
2019-10-30 10:44 ` Andreas Schwab
2019-10-30 10:55 ` Florian Weimer
2019-10-30 11:00 ` Andreas Schwab [this message]
2019-10-30 11:03 ` Florian Weimer
2019-10-30 11:10 ` Andreas Schwab
2019-10-30 12:01 ` Zack Weinberg
2019-10-30 16:20 ` Andreas Schwab
2019-10-30 16:31 ` Zack Weinberg
2019-10-30 16:47 ` Andreas Schwab
2019-10-30 16:58 ` Zack Weinberg
2019-10-30 17:26 ` Andreas Schwab
2019-10-30 18:12 ` Zack Weinberg
2019-10-30 18:36 ` Florian Weimer
2019-10-30 17:24 ` Joseph Myers
2019-11-28 9:43 ` Florian Weimer
2019-11-28 15:56 ` Carlos O'Donell
2019-11-28 15:58 ` Carlos O'Donell
2019-11-28 18:23 ` Rich Felker
2019-11-28 18:38 ` Szabolcs Nagy
2019-11-29 18:20 ` Martin Sebor
2019-11-27 19:08 ` Carlos O'Donell (Code Review)
2019-11-27 19:14 ` Florian Weimer (Code Review)
2019-11-27 22:11 ` Carlos O'Donell (Code Review)
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