module top();

  class c;

    string name;
    int    count;

    function new(string _name, int _count);
      name  = _name;
      count = _count;
    endfunction

    task t1();
      timer();
      $display("%t %s timer completed", $time, name);
    endtask

    task run();
      fork
        t1();
        disabler();
      join
    endtask

    task timer();
      $display("%t %s starting timer with count=%0d", $time, name, count);
      repeat(count) #1;
    endtask

    task disabler();
      repeat(count/2) #1;
      disable timer;
    endtask

  endclass

  class ex;

    c c1;
    c c2;

    function new();
      c1 = new("c1", 10);
      c2 = new("c2", 20);
    endfunction

    task run();
      fork
        c1.run();
        c2.run();
      join_none
    endtask

  endclass

  ex e = new;

  initial begin
    e.run();
  end

endmodule

0 c1 starting timer with count=10
               0 c2 starting timer with count=20
               5 c2 timer completed
               5 c1 timer completed

class c;
process p1;

task run();
  fork
    begin
      p1 = process::self(); //Get process of this begin..end block
      $display("%t %s starting timer with count=%0d", $time, name, count);
      repeat(count) #1;
    end
    disabler()
  join_none
endtask

task disabler();
  wait (p1 != null);
  repeat(count/2) #1;
  p1.kill();
endtask