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<title>5.12 Getting the current task's ID</title>
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<a name="1204834"> </a><font color="#003366" face="Verdana, Arial, Helvetica, sans-serif">5.12 Getting the current task's ID</font>
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<p>
<a name="1204835"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Several functions are provided for obtaining details of a specified task. The following function returns a pointer to the task structure of the current task:</font>
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<a name="1204837"> </a><font size=2 face=Courier><strong>task_t* task_id (void);<br></strong></font>
<p>
<a name="1204838"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">While <font size=2 face=Courier><strong>task_id</strong></font> is very efficient when called from a task, it takes a long time to execute when called from a high priority process, and cannot be called from an interrupt handler. To avoid these problems an alternative function is available:</font>
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<a name="1204840"> </a><font size=2 face=Courier><strong>task_context_t task_context(task_t** task, int* level);<br></strong></font>
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<a name="1204841"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">This returns whether it was called from a task, interrupt, or high priority process. In addition if <font size=2 face=Courier><strong>task</strong></font> is not <font size=2 face=Courier><strong>NULL</strong></font>, and <font size=2 face=Courier><strong>task_context</strong></font> is called from a task or high priority process, it assigns the current task ID to the <font size=2 face=Courier><strong>task_t</strong></font> pointed to by <font size=2 face=Courier><strong>task</strong></font>. Similarly if <font size=2 face=Courier><strong>level</strong></font> is not <font size=2 face=Courier><strong>NULL</strong></font>, and <font size=2 face=Courier><strong>task_context</strong></font> is called from an interrupt handler, then it assigns the current interrupt level to the <font size=2 face=Courier><strong>int</strong></font> pointed to by <font size=2 face=Courier><strong>level</strong></font>. The advantage in not requiring the current <font size=2 face=Courier><strong>task_t</strong></font> or interrupt level is that this function may operate considerably faster when this information does not have to be found.</font>
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<a name="1204844"> </a><font size=2 face="Verdana, Arial, Helvetica, sans-serif">Both of these function may be used in conjunction with <font size=2 face=Courier><strong>task_wait</strong></font>; see <a href="task17.htm#1204979"><font color="#0000ff" face="Verdana, Arial, Helvetica, sans-serif"><i>Section⌨️ 快捷键说明
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