bug-bash
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: builtin printf behaves incorrectly with "c and 'c character-value ar


From: Chet Ramey
Subject: Re: builtin printf behaves incorrectly with "c and 'c character-value arguments
Date: Mon, 05 Nov 2007 09:10:29 -0500
User-agent: Thunderbird 2.0.0.6 (Macintosh/20070728)

Rich Felker wrote:
> $ printf %d\\n \'À
> -61
> (expected 192)
> 
> This should be 192 regardless of locale on any system where wchar_t
> values are ISO-10646/Unicode. Bash is incorrectly reading the first
> byte of the UTF-8 which happens to be -61 when interpreted as signed
> char; on a Latin-1 based locale it will probably give -63 instead.
> 
> Both POSIX and common sense are clear that the numeric values
> resulting from 'c should be the wchar_t value of c and not the value
> of the first byte of the multibyte character; from the SUSv3 printf(1)
> documentation:
> 
>      Note that in a locale with multi-byte characters, the value of a
>      character is intended to be the value of the equivalent of the
>      wchar_t representation of the character as described in the
>      System Interfaces volume of IEEE Std 1003.1-2001.
> 
> Language lawyers could argue that on 'single-byte' locales perhaps the
> byte value should be used; however, strictly speaking a single-byte
> locale is simply a special case of a multi-byte one, and sanity should
> win in any case.

You're correct that the bash printf should understand multibyte characters
in a multibyte locale, but not that returning a multibyte character when
a user hasn't asked for one by setting the locale is more "sane."

Chet
-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                       Live Strong.  No day but today.
Chet Ramey, ITS, CWRU    address@hidden    http://cnswww.cns.cwru.edu/~chet/




reply via email to

[Prev in Thread] Current Thread [Next in Thread]