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<pre>STATUS SRSet
    (
    UINT32 sr
    )
</pre>

This routine sets the status register of a task that is not running;
that is, you must not call this-><b><i>SRSet</i>(&nbsp;)</b>.
Debugging facilities use this routine to set the trace bit in the 
status register of a task that is being single-stepped.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./VXWTask.html#top">VXWTask</a></b>

<hr>
<a name="VXWTask::statusString"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::statusString</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::statusString</i>(&nbsp;)</strong> - get task status as a string</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS statusString
    (
    char * pString
    ) const</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine deciphers the WIND task status word in the TCB for its
task, and copies the appropriate string to <i>pString</i>.
<p>
The formatted string is one of the following:
<p>
<table>
<tr valign=top>
<th align=left>String   </th><th align=left> Meaning</tr>
<tr><td colspan="2"><hr></tr>
<tr valign=top>
<td align=left>READY    </td><td align=left> Task is not waiting for any resource other than the CPU.</tr>
<tr valign=top>
<td align=left>PEND     </td><td align=left> Task is blocked due to the unavailability of some resource.</tr>
<tr valign=top>
<td align=left>DELAY    </td><td align=left> Task is asleep for some duration.</tr>
<tr valign=top>
<td align=left>SUSPEND  </td><td align=left> Task is unavailable for execution (but not suspended, delayed, or pended).</tr>
<tr valign=top>
<td align=left>DELAY+S  </td><td align=left> Task is both delayed and suspended.</tr>
<tr valign=top>
<td align=left>PEND+S   </td><td align=left> Task is both pended and suspended.</tr>
<tr valign=top>
<td align=left>PEND+T   </td><td align=left> Task is pended with a timeout.</tr>
<tr valign=top>
<td align=left>PEND+S+T </td><td align=left> Task is pended with a timeout, and also suspended.</tr>
<tr valign=top>
<td align=left>...+I  </td><td align=left> Task has inherited priority (+I may be appended to any string above).</tr>
<tr valign=top>
<td align=left>DEAD     </td><td align=left> Task no longer exists.</tr>
<tr valign=top>
<td align=left></tr>
</tr>

</table>

</blockquote><h4>RETURNS</h4><blockquote><p>
OK.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./VXWTask.html#top">VXWTask</a></b>

<hr>
<a name="VXWTask::suspend"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::suspend</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::suspend</i>(&nbsp;)</strong> - suspend task</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>    STATUS suspend ()</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine suspends its task.  Suspension is additive:  thus, tasks
can be delayed and suspended, or pended and suspended.  Suspended, delayed
tasks whose delays expire remain suspended.  Likewise, suspended,
pended tasks that unblock remain suspended only.
<p>
Care should be taken with asynchronous use of this facility.  The 
task is suspended regardless of its current state.  The task could, for
instance, have mutual exclusion to some system resource, such as the network
or system memory partition.  If suspended during such a time, the facilities
engaged are unavailable, and the situation often ends in deadlock.
<p>
This routine is the basis of the debugging and exception handling packages.
However, as a synchronization mechanism, this facility should be rejected 
in favor of the more general semaphore facility.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK, or ERROR if the task cannot be suspended.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./VXWTask.html#top">VXWTask</a></b>

<hr>
<a name="VXWTask::tcb"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::tcb</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::tcb</i>(&nbsp;)</strong> - get the task control block</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>    WIND_TCB * tcb ()</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine returns a pointer to the task control block (<b>WIND_TCB</b>) for
its task.  Although all task state information is contained in the
TCB, users must not modify it directly.  To change registers, for instance,
use <b><i><a href="./VXWTask.html#VXWTask::registers">VXWTask::registers</a></i>(&nbsp;)</b>.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
A pointer to a <b>WIND_TCB</b>.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./VXWTask.html#top">VXWTask</a></b>

<hr>
<a name="VXWTask::varAdd"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::varAdd</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::varAdd</i>(&nbsp;)</strong> - add a task variable to task</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS varAdd
    (
    int * pVar
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine adds a specified variable <i>pVar</i> (4-byte memory location) to
its task's context.  After calling this routine, the variable is
private to the task.  The task can access and modify the variable, but
the modifications are not visible to other tasks, and other tasks'
modifications to that variable do not affect the value seen by the
task.  This is accomplished by saving and restoring the variable's initial
value each time a task switch occurs to or from the calling task.
<p>
This facility can be used when a routine is to be spawned repeatedly as
several independent tasks.  Although each task has its own stack,
and thus separate stack variables, they all share the same static and
global variables.  To make a variable <i>not</i> shareable, the routine can
call <b><i><a href="./VXWTask.html#VXWTask::varAdd">VXWTask::varAdd</a></i>(&nbsp;)</b> to make a separate copy of the variable for each
task, but all at the same physical address.
<p>
Note that task variables increase the task switch time to and from the
tasks that own them.  Therefore, it is desirable to limit the number of
task variables that a task uses.  One efficient way to use task variables 
is to have a single task variable that is a pointer to a dynamically 
allocated structure containing the task's private data.
<p>
</blockquote><h4>EXAMPLE</h4><blockquote><p>
<p>
Assume that three identical tasks are spawned with a main routine called
<i><b><i>operator</i>(&nbsp;)</b></i>.  All three use the structure <b>OP_GLOBAL</b> for all variables
that are specific to a particular incarnation of the task.  The following
code fragment shows how this is set up:
<p>
<pre>OP_GLOBAL *opGlobal;  // ptr to operator task's global variables
VXWTask   me;         // task object for self

void operator
    (
    int opNum         // number of this operator task 
    )
    {
    me = VXWTask (0); // task object for running task
    if (me.varAdd ((int *)&amp;opGlobal) != OK)
        {
        printErr ("operator%d: can't VXWTask::varAdd opGlobal\n", opNum);
        me.suspend ();
        }

    if ((opGlobal = (OP_GLOBAL *) malloc (sizeof (OP_GLOBAL))) == NULL)
        {
        printErr ("operator%d: can't malloc opGlobal\n", opNum);
        me.suspend ();
        }
    ...
    }
</pre>

</blockquote><h4>RETURNS</h4><blockquote><p>
<p>
OK, or ERROR if memory is insufficient for the task variable descriptor.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><i><a href="./VXWTask.html#VXWTask::varDelete">VXWTask::varDelete</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varGet">VXWTask::varGet</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varSet">VXWTask::varSet</a></i>(&nbsp;)</b>

<hr>
<a name="VXWTask::varDelete"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::varDelete</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::varDelete</i>(&nbsp;)</strong> - remove a task variable from task</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS varDelete
    (
    int * pVar
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine removes a specified task variable, <i>pVar</i>, from its
task's context.  The private value of that variable is lost.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK, or
ERROR if the task variable does not exist for the task.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><i><a href="./VXWTask.html#VXWTask::varAdd">VXWTask::varAdd</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varGet">VXWTask::varGet</a></i>(&nbsp;)</b>, <b><i>VXWTask:varSet</i>(&nbsp;)</b>

<hr>
<a name="VXWTask::varGet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::varGet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::varGet</i>(&nbsp;)</strong> - get the value of a task variable</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int varGet
    (
    int * pVar
    ) const</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine returns the private value of a task variable for its
task.  The task is usually not the calling task,
which can get its private value by directly accessing the variable.
This routine is provided primarily for debugging purposes.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
<p>
The private value of the task variable, or
ERROR if the task does not own the task variable.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><i><a href="./VXWTask.html#VXWTask::varAdd">VXWTask::varAdd</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varDelete">VXWTask::varDelete</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varSet">VXWTask::varSet</a></i>(&nbsp;)</b>

<hr>
<a name="VXWTask::varInfo"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::varInfo</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::varInfo</i>(&nbsp;)</strong> - get a list of task variables</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int varInfo
    (
    TASK_VAR varList[],
    int      maxVars
    ) const</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine provides the calling task with a list of all of the task
variables of its task.  The unsorted array of task variables is
copied to <i>varList</i>.
<p>
</blockquote><h4>CAVEATS</h4><blockquote><p>
Kernel rescheduling is disabled while task variables are
looked up.  
<p>
There is no guarantee that all the task variables are still
valid or that new task variables have not been created by the time this
routine returns.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of task variables in the list.
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./VXWTask.html#top">VXWTask</a></b>

<hr>
<a name="VXWTask::varSet"></a>
<p align=right>
<a href="rtnIndex.html"><i>Wind Foundation Classes :  Methods</i></a></p>

</blockquote><h1><i>VXWTask::varSet</i>(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong><i>VXWTask::varSet</i>(&nbsp;)</strong> - set the value of a task variable</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS varSet
    (
    int * pVar,
    int   value
    )</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sets the private value of the task variable for a specified
task.  The specified task is usually not the calling task, which can set
its private value by directly modifying the variable.  This routine is
provided primarily for debugging purposes.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
<p>
OK, or ERROR if the task does not own the task variable.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><i><a href="./VXWTask.html#VXWTask::varAdd">VXWTask::varAdd</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varDelete">VXWTask::varDelete</a></i>(&nbsp;)</b>, <b><i><a href="./VXWTask.html#VXWTask::varGet">VXWTask::varGet</a></i>(&nbsp;)</b>

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