xnu-7195.101.1.tar.gz

[apple/xnu.git] / osfmk / man / device_get_status.html

<h2>device_get_status</h2>
<hr>
<p>
<strong>Function</strong> - Return the current device status.
<h3>SYNOPSIS</h3>
<pre>
<strong>#include&lt device/device.h&gt</strong>

<strong>kern_return_t   device_get_status</strong>
                <strong>(mach_port_t</strong>                             <var>device</var>,
                 <strong>dev_flavor_t</strong>                            <var>flavor</var>,
                 <strong>dev_status_t</strong>                            <var>status</var>,
                 <strong>mach_msg_type_number_t</strong>           <var>*status_count</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>device</var> 
<dd>
[in device send right]
A device port to the device to be interrogated.
<p>
<dt> <var>flavor</var> 
<dd>
[in scalar]
The type of status information requested.
<p>
<dt> <var>status</var> 
<dd>
[out array of natural-sized units]
The returned device status.
<p>
<dt> <var>status_count</var> 
<dd>
[pointer to in/out scalar]
On input, the reserved size of <var>status</var>; on
output, the size of the returned device status (in natural-sized units).
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>device_get_status</strong> function returns status information
pertaining to an open device.  The possible values for <var>flavor</var> as well 
as the meaning of the returned status information is device dependent.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>D_DEVICE_DOWN</strong>
<dd>
Device has been shut down
<p>
<dt> <strong>D_NO_SUCH_DEVICE</strong>
<dd>
No device with that name, or the device is not operational.
<p>
<dt> <strong>D_OUT_OF_BAND</strong>
<dd>
Out-of-band condition occurred on device (such as typing \*L<Ctrl>-C\*O)
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="device_set_status.html"><strong>device_set_status</strong></a>.