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<a name="1204939"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">5.15 Task termination</font>
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<p>
<a name="1204940"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A task terminates when it returns from the task's entry point function.</font>
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<a name="1204941"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">A task may also terminate by using the following function:</font>
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<a name="1204943"> </a><font size=2 face=Courier><strong>void task_exit(int param);<br></strong></font>
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<a name="1204944"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">In both cases an exit status can be specified. When the task returns from its entry point function, the exit status is the value that the function returns. If <font size=2 face=Courier><strong>task_exit</strong></font> is called then the exit status is specified as the parameter. This value is then made available to the "onexit" handler if one has been installed (see below).</font>
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<a name="1204945"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Just before the task terminates (either by returning from its entry point function, or calling <font size=2 face=Courier><strong>task_exit</strong></font>), it calls an onexit handler. This function allows any application specific tidying up to be performed before the task terminates. The onexit handler is installed by calling:</font>
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<a name="1204947"> </a><font size=2 face=Courier><strong>task_onexit_fn_t task_onexit_set(task_onexit_fn_t fn);<br></strong></font>
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<a name="1204948"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The onexit handler function must have a prototype of:</font>
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<a name="1204949"> </a><font size=2 face=Courier><strong>void onexit_handler(task_t *task, int param)<br></strong></font>
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<a name="1204950"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">When the handler function is called, <font size=2 face=Courier><strong>task</strong></font> specifies the task which has exited, and <font size=2 face=Courier><strong>param</strong></font> is the task's exit status.</font>
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<a name="1204951"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The function <font size=2 face=Courier><strong>task_onexit_set_sl</strong></font> is provided to set the task onexit handler and specify a static link.</font>
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<p>
<a name="1204952"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">The following code example shows how a task's exit code can be stored in its task-data (see <a href="task15.htm#1204893"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>Section⌨️ 快捷键说明
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