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(python2.1-lib.info)Scheduler Objects

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Enter node , (file) or (file)node

Scheduler Objects
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`scheduler' instances have the following methods:

`enterabs(time, priority, action, argument)'
     Schedule a new event. The TIME argument should be a numeric type
     compatible with the return value of the TIMEFUNC function passed
     to the constructor. Events scheduled for the same TIME will be
     executed in the order of their PRIORITY.

     Executing the event means executing `apply(ACTION, ARGUMENT)'.
     ARGUMENT must be a tuple holding the parameters for ACTION.

     Return value is an event which may be used for later cancellation
     of the event (see `cancel()').

`enter(delay, priority, action, argument)'
     Schedule an event for DELAY more time units. Other then the
     relative time, the other arguments, the effect and the return value
     are the same as those for `enterabs()'.

`cancel(event)'
     Remove the event from the queue. If EVENT is not an event
     currently in the queue, this method will raise a `RuntimeError'.

`empty()'
     Return true if the event queue is empty.

`run()'
     Run all scheduled events. This function will wait (using the
     `delayfunc' function passed to the constructor) for the next
     event, then execute it and so on until there are no more scheduled
     events.

     Either ACTION or DELAYFUNC can raise an exception.  In either
     case, the scheduler will maintain a consistent state and propagate
     the exception.  If an exception is raised by ACTION, the event
     will not be attempted in future calls to `run()'.

     If a sequence of events takes longer to run than the time available
     before the next event, the scheduler will simply fall behind.  No
     events will be dropped; the calling code is responsible for
     canceling events which are no longer pertinent.