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<H1><A NAME="SECTION0081200000000000000000">
6.12 <tt class="module">sched</tt> --
         Event scheduler</A>
</H1>

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<A NAME="module-sched"></A>

<P>
The <tt class="module">sched</tt> module defines a class which implements a general
purpose event scheduler:<a id='l2h-1981' xml:id='l2h-1981'></a>

<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><span class="typelabel">class</span>&nbsp;<tt id='l2h-1980' xml:id='l2h-1980' class="class">scheduler</tt></b>(</nobr></td>
  <td><var>timefunc, delayfunc</var>)</td></tr></table></dt>
<dd>
The <tt class="class">scheduler</tt> class defines a generic interface to scheduling
events. It needs two functions to actually deal with the ``outside world''
-- <var>timefunc</var> should be callable without arguments, and return
a number (the ``time'', in any units whatsoever).  The <var>delayfunc</var>
function should be callable with one argument, compatible with the output
of <var>timefunc</var>, and should delay that many time units.
<var>delayfunc</var> will also be called with the argument <code>0</code> after
each event is run to allow other threads an opportunity to run in
multi-threaded applications.
</dl>

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Example:

<P>
<div class="verbatim"><pre>
&gt;&gt;&gt; import sched, time
&gt;&gt;&gt; s=sched.scheduler(time.time, time.sleep)
&gt;&gt;&gt; def print_time(): print "From print_time", time.time()
...
&gt;&gt;&gt; def print_some_times():
...     print time.time()
...     s.enter(5, 1, print_time, ())
...     s.enter(10, 1, print_time, ())
...     s.run()
...     print time.time()
...
&gt;&gt;&gt; print_some_times()
930343690.257
From print_time 930343695.274
From print_time 930343700.273
930343700.276
</pre></div>

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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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