How does forever behaves in fork block

SystemVerilog
10

In reply to Jyothsna:

Can’t help you without knowing the timing of ‘flag1’ and the value of ‘duration’. Also, a better way of modeling what they wanted is

 forever begin
    fork
       begin
         wait(flag1==1); 
         $display("flag1 asserted");
         #(duration);
         flag2 = 1;
       end
       @negedge flag1;
    join_any
    disable fork;
  end