ref: cb31a80ef0c5eafd2a6e338397134c503b3f8b19
dir: /libc/src/isalnum.c/
/* See LICENSE file for copyright and license details. */ #define __USE_MACROS #include <ctype.h> #undef isalnum int isalnum(int c) { return _ctype[(unsigned char) c] & (_U|_L|_D); }