On Mon, Nov 05, 2007 at 09:10:29AM -0500, Chet Ramey wrote: > 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."
I'm not sure what you mean. For a Latin-1 locale there is no difference, but if the locale is a different legacy locale, the wchar_t value (Unicode scalar value on systems with __STDC_ISO_10646__ defined) needs to be returned. If you're doubtful about the intent of the standard, why not file a request for interpretation? Rich
