This function uses the Gamma send_async function to send executable code to the Controller. This sends an message asynchronously, which allows this function to continue without waiting for a reply from the Controller. This breaks a potential feedback loop, because the Controller also sends messages (start and stop) to the Monitor.

   /*--------------------------------------------------------------------
    * Function:    send_message
    * Returns:     t or nil
    * Description: Sends information messages for the Controller's text box.
    *              The text of the messages is stored in the file
    *              'messages.txt'.
    *------------------------------------------------------------------*/
   function send_message(msg)
   {
     local tsk;
     if ((tsk = locate_task("control", t)) != nil)
       {
         if(msg == "nsnames")
             send_async(tsk, `show_names(text2));
         else
             send_async(tsk, `anygui_show_text(text, read_msg(@msg), 1));
         close_task(tsk);
       }
   }
   

This started_died_hook function is run whenever a task starts or dies, and is used to update the Process Status display. The multiple-length optional argument (see Function Arguments in the Gamma manual) allows for multiple tasks starting and stopping.

   /*--------------------------------------------------------------------
    * Function:    started_died_hook
    * Returns:     t or nil
    * Description: Called whenever a task starts or dies, this function 
    *              calls send_message() to change the process status display.
    *              Gets added to the Controller from within the
    *              program_startup() function.
    *------------------------------------------------------------------*/
   function started_died_hook(!a?...=nil)
   {
     send_message("nsnames");
   }