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Re: Should memchr work with invalid data size?

From: Andreas Schwab <schwab at suse dot de>
To: Florian Weimer <fw at deneb dot enyo dot de>
Cc: "H.J. Lu" <hjl dot tools at gmail dot com>, GNU C Library <libc-alpha at sourceware dot org>
Date: Thu, 18 May 2017 09:42:38 +0200
Subject: Re: Should memchr work with invalid data size?
Authentication-results: sourceware.org; auth=none
References: <CAMe9rOoZfLVq5_K1Nz16FuH50FBHSvE4J3cFysQBYC_Bxpq9sw@mail.gmail.com> <8737c2r9to.fsf@mid.deneb.enyo.de>

On Mai 18 2017, Florian Weimer <fw@deneb.enyo.de> wrote:

> POSIX is more clear:
>
> | Implementations shall behave as if they read the memory byte by byte
> | from the beginning of the bytes pointed to by s and stop at the
> | first occurrence of c (if it is found in the initial n bytes).
>
> This language is not found in C99.

In C11 it has been amended and says basically the same:

"The implementation shall behave as if it reads the characters
sequentially and stops as soon as a matching character is found."

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."

Follow-Ups:
- Re: Should memchr work with invalid data size?
  - From: Adhemerval Zanella

References:
- Should memchr work with invalid data size?
  - From: H.J. Lu
- Re: Should memchr work with invalid data size?
  - From: Florian Weimer

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