@node isascii
@section @code{isascii}
@findex isascii

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

Gnulib module: ctype

Portability problems fixed by Gnulib:
@itemize
@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
POSIX says this function is obsolescent and it is planned to be
removed in POSIX 202x.
@end itemize

Note: This function's behaviour depends on the locale, but requires special
handling for the multibyte characters that occur in strings in locales with
@code{MB_CUR_MAX > 1} (this includes all the common UTF-8 locales).
There are two alternative APIs:

@table @code
@item c_isascii
This function operates in a locale independent way and returns true only for
ASCII characters.  It is provided by the Gnulib module @samp{c-ctype}.

@item mb_isascii
This function operates in a locale dependent way, on multibyte characters.
It is provided by the Gnulib module @samp{mbchar}.
@end table