1 #include <string.h>
2 
strncat(char * restrict d,const char * restrict s,size_t n)3 char* strncat(char* restrict d, const char* restrict s, size_t n) {
4     char* a = d;
5     d += strlen(d);
6     while (n && *s)
7         n--, *d++ = *s++;
8     *d++ = 0;
9     return a;
10 }
11