ref: bc1d0b048c6c8de00d0b6362ce9a1a624f35349d dir: /libc/src/toupper.c/
/* See LICENSE file for copyright and license details. */ #define __USE_MACROS #include <ctype.h> #undef toupper int toupper(int c) { return (islower(c)) ? c & ~0x20 : c; }