ref: 32bc8b570e96d2735d23bba6375cb2d2443b2d85
dir: /lib/c/strncat.c/
#include <string.h>
#undef strncat
char *
strncat(char * restrict dst, const char * restrict src, size_t n)
{
char *ret = dst;
while (*dst)
++dst;
while (n-- > 0 && *src)
*dst++ = *src++;
*dst = '\0';
return ret;
}