// $Id: TaskScheduler.nc,v 1.1 2008/06/12 14:02:42 klueska Exp $
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/** 
  * The interface to a TinyOS task scheduler.
  *
  * @author Philip Levis
  * @author Kevin Klues <klueska@cs.stanford.edu>
  * @date   January 19 2005
  * @see TEP 106: Tasks and Schedulers
  * @see TEP 107: Boot Sequence
  */ 


interface TaskScheduler {

  /** 
   * Initialize the scheduler.
   */
  command void init();

  /** 
    * Run the next task if one is waiting, otherwise return immediately. 
    *
    * @return        whether a task was run -- TRUE indicates a task
    *                ran, FALSE indicates there was no task to run.
    */
  command bool runNextTask();
  
  /** 
    * Check to see if there are any pending tasks in the task queue. 
    *
    * @return        whether there are any tasks waiting to run
    */
  async command bool hasTasks();

  /**
   * Enter an infinite task-running loop. Put the MCU into a low power
   * state when the processor is idle (task queue empty, waiting for
   * interrupts). This call never returns.
   */
  command void taskLoop();
}