ref: 12934f8fb43662ca8bc906caaad5f5e8ccbb6bc1
dir: /lib/c/string/memchr.c/
#include <string.h> #undef memchr void * memchr(const void *s, int c, size_t n) { const unsigned char *bp = s; while (n > 0 && *bp++ != c) --n; return (n == 0) ? NULL : bp-1; }