@node towupper
@section @code{towupper}
@findex towupper

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/towupper.html}

Gnulib module: wctype-h

Portability problems fixed by Gnulib:
@itemize
@item
This function returns values of which the upper 16 bits are incorrect
on some platforms:
mingw.
@item
This function cannot be called from plain inline or extern inline functions
on some platforms:
OS X 10.8.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
On AIX and Windows platforms, @code{wchar_t} is a 16-bit type and therefore cannot
accommodate all Unicode characters.
@end itemize