international upper- and lowercase (was: locales)

[Karl Heuer]

In article <3231 at cbosgd.ATT.COM> mark at cbosgd.ATT.COM (Mark Horton) writes:
>What is the toupper function supposed to do when presented with an ess-tset
>[which is a German letter with no uppercase equivalent]?

The way I read it, toupper returns its argument unchanged if it isn't
lowercase, or if it has no uppercase equivalent.

On a related note: In the May86 Draft (which predates setlocale(), so this is
probably all out of date now) I read that isalpha tests for "any character for
which isupper or islower is true, or any of an implementation-defined set of
[other characters]".  Are there any alphabets that contain letters that are
considered neither uppercase nor lowercase?  (If so, the usual trick of or'ing
the isupper and islower bits together wouldn't work.)

Karl W. Z. Heuer (ima!haddock!karl or karl at haddock.isc.com), The Walking Lint