1  char buf[40];
       2  
       3  extern int sprintf (char*, const char*, ...);
       4  extern void abort (void);
       5  
       6  int main()
       7  {
       8    int i = 0;
       9    int l = sprintf (buf, "%s", i++ ? "string" : "other string");
      10    if (l != sizeof ("other string") - 1 || i != 1)
      11      abort ();
      12    return 0;
      13  }
      14