1#include <string.h>
 2
 3char *strncat(char *restrict d, const char *restrict s, size_t n)
 4{
 5	char *a = d;
 6	d += strlen(d);
 7	while (n && *s) n--, *d++ = *s++;
 8	*d++ = 0;
 9	return a;
10}