Re: ascii string comparison [Re: use C locale for LC_CTYPE]

Jorge wrote:
> On Mon, Oct 31, 2011 at 04:03:38AM +0000, corvid wrote:
> > Jorge wrote:
> > >   From a distance this global change looks to me like exposing ourselves
> > > to more troubles. In other words, why not:
> > > 
> > >      int dStrcasecmp(...)
> > >      {
> > >         if (locale has special rules)
> > >            special treatment
> > >         else
> > >            strcasecmp(...)
> > >      }
> > > 
> > >   Disclaimer: I haven't studied the problem in detail.
> > 
> > Having to know about the locales would be trouble.
> > Judging by the wikipedia page, we'd have to look for 'tr' and 'az'
> > for sure, and they've been considering switching back to Latin
> > script in Kazakhstan, and probably not Tatar because they're mostly
> > Cyrillic, but probably yes to Crimean Tatar because it looks like
> > they're a bit more Latin than Cyrillic at the moment.
> > 
> > So it's a touchy enough situation that different libc's may have
> > different ideas of it all, and individual ones will change as
> > circumstances change,
> 
>   If libc has not nailed it already, it must be hard to solve
> the problem in a generic way.

There are strcasecmp_l() and strncasecmp_l(), but they were only
introduced in a very recent version of posix.

http://www.gnu.org/s/hello/manual/gnulib/strcasecmp_005fl.html
says "This function is missing on many platforms: MacOS X 10.3,
FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, IRIX 6.5,
OSF/1 5.1, Solaris 11 2010-11, Cygwin, mingw, Interix 3.5, BeOS."

As for whether strcasecmp_l() is cheap, in any case, I don't know.