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| 55 | <H1><A NAME="SECTION0081200000000000000000"> |
| 56 | 6.12 <tt class="module">sched</tt> -- |
| 57 | Event scheduler</A> |
| 58 | </H1> |
| 59 | |
| 60 | <P> |
| 61 | <A NAME="module-sched"></A> |
| 62 | |
| 63 | <P> |
| 64 | The <tt class="module">sched</tt> module defines a class which implements a general |
| 65 | purpose event scheduler:<a id='l2h-1981' xml:id='l2h-1981'></a> |
| 66 | |
| 67 | <P> |
| 68 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> |
| 69 | <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-1980' xml:id='l2h-1980' class="class">scheduler</tt></b>(</nobr></td> |
| 70 | <td><var>timefunc, delayfunc</var>)</td></tr></table></dt> |
| 71 | <dd> |
| 72 | The <tt class="class">scheduler</tt> class defines a generic interface to scheduling |
| 73 | events. It needs two functions to actually deal with the ``outside world'' |
| 74 | -- <var>timefunc</var> should be callable without arguments, and return |
| 75 | a number (the ``time'', in any units whatsoever). The <var>delayfunc</var> |
| 76 | function should be callable with one argument, compatible with the output |
| 77 | of <var>timefunc</var>, and should delay that many time units. |
| 78 | <var>delayfunc</var> will also be called with the argument <code>0</code> after |
| 79 | each event is run to allow other threads an opportunity to run in |
| 80 | multi-threaded applications. |
| 81 | </dl> |
| 82 | |
| 83 | <P> |
| 84 | Example: |
| 85 | |
| 86 | <P> |
| 87 | <div class="verbatim"><pre> |
| 88 | >>> import sched, time |
| 89 | >>> s=sched.scheduler(time.time, time.sleep) |
| 90 | >>> def print_time(): print "From print_time", time.time() |
| 91 | ... |
| 92 | >>> def print_some_times(): |
| 93 | ... print time.time() |
| 94 | ... s.enter(5, 1, print_time, ()) |
| 95 | ... s.enter(10, 1, print_time, ()) |
| 96 | ... s.run() |
| 97 | ... print time.time() |
| 98 | ... |
| 99 | >>> print_some_times() |
| 100 | 930343690.257 |
| 101 | From print_time 930343695.274 |
| 102 | From print_time 930343700.273 |
| 103 | 930343700.276 |
| 104 | </pre></div> |
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