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vxworks相关论文

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<div class="CellBody"><a name="84052"> </a><b class="symbol_UC">VX_FP_TASK </b>&nbsp;</div>
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<div class="CellBody"><a name="84054"> </a>0x8&nbsp;</div>
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<div class="CellBody"><a name="84056"> </a>Execute with the floating-point coprocessor.&nbsp;</div>
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<div class="CellBody"><a name="84059"> </a><b class="symbol_UC">VX_NO_STACK_FILL</b> &nbsp;</div>
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<div class="CellBody"><a name="84061"> </a>0x100&nbsp;</div>
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<div class="CellBody"><a name="84064"> </a>Do not fill stack with 0xee.&nbsp;</div>
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<div class="CellBody"><a name="84067"> </a><b class="symbol_UC">VX_PRIVATE_ENV </b>&nbsp;</div>
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<div class="CellBody"><a name="84069"> </a>0x80&nbsp;</div>
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<div class="CellBody"><a name="84071"> </a>Execute task with a private environment.&nbsp;</div>
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<div class="CellBody"><a name="84074"> </a><b class="symbol_UC">VX_UNBREAKABLE</b> &nbsp;</div>
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<div class="CellBody"><a name="84076"> </a>0x2&nbsp;</div>
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<div class="CellBody"><a name="84078"> </a>Disable breakpoints for the task.&nbsp;</div>
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<dd><p class="Body"><a name="84085"> </a>To create a task that includes floating-point operations, use:</p>
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<dd><pre class="Code2"><b><a name="84086">tid = taskSpawn ("tMyTask", 90, VX_FP_TASK, 20000, myFunc, 2387, 0, 0, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0, 0, 0, 0, 0, 0, 0);</a></b></pre>
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<dd><p class="Body"><a name="84087"> </a>Task options can also be examined and altered after a task is spawned by means of the routines listed in <a href="c-basic3.html#84094">Table&nbsp;2-6</a>. Currently, only the <b class="symbol_UC">VX_UNBREAKABLE</b> option can be altered.<p class="table">
<h4 class="EntityTitle"><a name="84094"><font face="Helvetica, sans-serif" size="-1" class="sans">Table 2-6:&nbsp;&nbsp;Task Option Routines</font></a></h4>

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<div class="CellBody"><a name="84107"> </a><b class="routine"><i class="routine">taskOptionsGet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84109"> </a>Examine task options.&nbsp;</div>
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<div class="CellBody"><a name="84112"> </a><b class="routine"><i class="routine">taskOptionsSet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84115"> </a>Set task options.&nbsp;</div>
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<h4 class="H4"><i><a name="84121">Task Information</a></i></h4>
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<dd><p class="Body"><a name="84125"> </a>The routines listed in <a href="c-basic3.html#84129">Table&nbsp;2-7</a> get information about a task by taking a snapshot of a task's context when called. The state of a task is dynamic, and the information may not be current unless the task is known to be dormant (that is, suspended).<p class="table">
<h4 class="EntityTitle"><a name="84129"><font face="Helvetica, sans-serif" size="-1" class="sans">Table 2-7:&nbsp;&nbsp;Task Information Routines</font></a></h4>

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<div class="CellBody"><a name="84142"> </a><b class="routine"><i class="routine">taskIdListGet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84144"> </a>Fill an array with the IDs of all active tasks.&nbsp;</div>
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<div class="CellBody"><a name="84147"> </a><b class="routine"><i class="routine">taskInfoGet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84149"> </a>Get information about a task.&nbsp;</div>
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<div class="CellBody"><a name="84152"> </a><b class="routine"><i class="routine">taskPriorityGet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84154"> </a>Examine the priority of a task.&nbsp;</div>
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<div class="CellBody"><a name="84158"> </a><b class="routine"><i class="routine">taskRegsGet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84160"> </a>Examine a task's registers.&nbsp;</div>
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<div class="CellBody"><a name="84163"> </a><b class="routine"><i class="routine">taskRegsSet</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84165"> </a>Set a task's registers.&nbsp;</div>
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<div class="CellBody"><a name="84168"> </a><b class="routine"><i class="routine">taskIsSuspended</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84170"> </a>Check if a task is suspended.&nbsp;</div>
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<div class="CellBody"><a name="84173"> </a><b class="routine"><i class="routine">taskIsReady</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84175"> </a>Check if a task is ready to run.&nbsp;</div>
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<div class="CellBody"><a name="84178"> </a><b class="routine"><i class="routine">taskTcb</i></b><b>(&nbsp;)</b> &nbsp;</div>
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<div class="CellBody"><a name="84181"> </a>Get a pointer to task's control block.&nbsp;</div>
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<h4 class="H4"><i><a name="84187">Task Deletion and Deletion Safety</a></i></h4>
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<dd><p class="Body"><a name="84188"> </a>Tasks can be dynamically deleted from the system. VxWorks includes the routines listed in <a href="c-basic3.html#92586">Table&nbsp;2-8</a> to delete tasks and protect tasks from unexpected deletion.</p>
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<hr><div class="CalloutCell"><a name="92575"><b class="symbol_UC"><font face="Helvetica, sans-serif" size="-1" class="sans">WARNING:  </font></b></a>Make sure that tasks are not deleted at inappropriate times: a task must release all shared resources it holds before an application deletes the task.</div>
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<dd><p class="Body"><a name="84235"> </a>Tasks implicitly call <b class="routine"><i class="routine">exit</i></b><b>(&nbsp;)</b> if the entry routine specified during task creation returns. Alternatively, a task can explicitly call <b class="routine"><i class="routine">exit</i></b><b>(&nbsp;)</b> at any point to kill itself. A task can kill another task by calling <b class="routine"><i class="routine">taskDelete</i></b><b>(&nbsp;)</b>.<p class="table">
<h4 class="EntityTitle"><a name="92586"><font face="Helvetica, sans-serif" size="-1" class="sans">Table 2-8:&nbsp;&nbsp;Task-Deletion Routines</font></a></h4>

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