@node mbtowc
@section @code{mbtowc}
@findex mbtowc

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

Gnulib module: mbtowc

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
Android 4.4.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
In UTF-8 locales, this function may return wide characters up to 0x7FFFFFFF
(that is, beyond 0x0010FFFF) on some platforms:
@c https://sourceware.org/bugzilla/show_bug.cgi?id=2373
@c https://sourceware.org/bugzilla/show_bug.cgi?id=26034
glibc 2.34.
@item
This function accumulates hidden state on some platforms:
glibc 2.8 (see @url{https://sourceware.org/bugzilla/show_bug.cgi?id=9674}).
@item
On Windows and 32-bit AIX platforms, @code{wchar_t} is a 16-bit type and therefore cannot
accommodate all Unicode characters.
@end itemize