void main(){  short x[4];   x[0] = x[1] = 1;  if (getgroups(1,x) == 0) if (setgroups(1,x) == -1) _exit(1);   if (getgroups(1,x) == -1) _exit(1);  if (x[1] != 1) _exit(1);  x[1] = 2;  if (getgroups(1,x) == -1) _exit(1);  if (x[1] != 2) _exit(1);  _exit(0);}