1 void main()

     2 {

     3   short x[4];

     4  

     5   x[0] = x[1] = 1;

     6   if (getgroups(1,x) == 0) if (setgroups(1,x) == -1) _exit(1);

     7  

     8   if (getgroups(1,x) == -1) _exit(1);

     9   if (x[1] != 1) _exit(1);

    10   x[1] = 2;

    11   if (getgroups(1,x) == -1) _exit(1);

    12   if (x[1] != 2) _exit(1);

    13   _exit(0);

    14 }