master
 1#include <wchar.h>
 2
 3size_t wcscspn(const wchar_t *s, const wchar_t *c)
 4{
 5	const wchar_t *a;
 6	if (!c[0]) return wcslen(s);
 7	if (!c[1]) return (s=wcschr(a=s, *c)) ? s-a : wcslen(a);
 8	for (a=s; *s && !wcschr(c, *s); s++);
 9	return s-a;
10}