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cpython_sandbox / Doc / library / sched.rst

:mod:`sched` --- Event scheduler

Source code: :source:`Lib/sched.py`


The :mod:`sched` module defines a class which implements a general purpose event scheduler:

The :class:`scheduler` class defines a generic interface to scheduling events. It needs two functions to actually deal with the "outside world" --- timefunc should be callable without arguments, and return a number (the "time", in any units whatsoever). If time.monotonic is not available, the timefunc default is time.time instead. The delayfunc function should be callable with one argument, compatible with the output of timefunc, and should delay that many time units. delayfunc will also be called with the argument 0 after each event is run to allow other threads an opportunity to run in multi-threaded applications.

Example:

>>> import sched, time
>>> s = sched.scheduler(time.time, time.sleep)
>>> def print_time(a='default'):
...     print("From print_time", time.time(), a)
...
>>> def print_some_times():
...     print(time.time())
...     s.enter(10, 1, print_time)
...     s.enter(5, 2, print_time, argument=('positional',))
...     s.enter(5, 1, print_time, kwargs={'a': 'keyword'})
...     s.run()
...     print(time.time())
...
>>> print_some_times()
930343690.257
From print_time 930343695.274 positional
From print_time 930343695.275 keyword
From print_time 930343700.273 default
930343700.276

Scheduler Objects

:class:`scheduler` instances have the following methods and attributes: