+
−@node isdigit
+
−@section @code{isdigit}
+
−@findex isdigit
+
−
+
−POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/isdigit.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
+
−@end itemize
+
−
+
−Note: This function's behaviour depends on the locale, but does not support
+
−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 four alternative APIs:
+
−
+
−@table @code
+
−@item c_isdigit
+
−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 iswdigit
+
−This function operates in a locale dependent way, on wide characters.  In
+
−order to use it, you first have to convert from multibyte to wide characters,
+
−using the @code{mbrtowc} function.  It is provided by the Gnulib module
+
−@samp{wctype}.
+
−
+
−@item mb_isdigit
+
−This function operates in a locale dependent way, on multibyte characters.
+
−It is provided by the Gnulib module @samp{mbchar}.
+
−
+
−@item uc_is_digit
+
−This function operates in a locale independent way, on Unicode characters.
+
−It is provided by the Gnulib module @samp{unictype/ctype-digit}.
+
−@end table