osfmk/man/device_write_inband.html

   1 <h2>device_write_inband</h2>
<hr>
<p>
<strong>Function</strong> - Write a sequence of bytes "inband" to a device object.
<h3>SYNOPSIS</h3>
<pre>
<strong>#include&ltdevice/device.h (device_write_inband)&gt</strong>

<strong>kern_return_t   device_write_inband</strong>
                <strong>(mach_port_t</strong>                             <var>device</var>,
                 <strong>dev_mode_t</strong>                                <var>mode</var>,
                 <strong>recnum_t</strong>                                <var>recnum</var>,
                 <strong>io_buf_ptr_inband_t</strong>                       <var>data</var>,
                 <strong>mach_msg_type_number_t</strong>              <var>data_count</var>,
                 <strong>io_buf_len_t</strong>                      <var>io_buf_len_t</var><strong>);</strong>


<strong>#include&ltdevice/device_request.h&gt</strong>

<strong>kern_return_t   device_write_request_inband</strong>
                <strong>(mach_port_t</strong>                             <var>device</var>,
                 <strong>mach_port_t</strong>                         <var>reply_port</var>,
                 <strong>dev_mode_t</strong>                                <var>mode</var>,
                 <strong>recnum_t</strong>                                <var>recnum</var>,
                 <strong>io_buf_ptr_inband_t</strong>                       <var>data</var>,
                 <strong>mach_msg_type_number_t</strong>              <var>data_count</var><strong>);</strong>


<strong>kern_return_t   ds_device_write_reply_inband</strong>
                <strong>(mach_port_t</strong>                         <var>reply_port</var>,
                 <strong>kern_return_t</strong>                      <var>return_code</var>,
                 <strong>io_buf_len_t</strong>                      <var>bytes_writte</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 written.
<p>
<dt> <var>reply_port</var> 
<dd>
[in reply receive (to be converted to send-once) right]
The port to 
which the reply message is to be sent.
<p>
<dt> <var>mode</var> 
<dd>
[in scalar]
I/O mode value.  Meaningful options are:
<dl>
<p>
<dt> <strong>D_NOWAIT</strong>
<dd>
Do not wait for I/O completion.
</dl>
<p>
<dt> <var>recnum</var> 
<dd>
[in scalar]
Record number to be written.
<p>
<dt> <var>data</var> 
<dd>
[pointer to in array of bytes]
Data bytes to be written.
<p>
<dt> <var>data_count</var> 
<dd>
[in scalar]
Number of data bytes to be written.
<p>
<dt> <var>return_code</var> 
<dd>
[in scalar]
The return status code from the write.
<p>
<dt> <var>bytes_written</var> 
<dd>
[out scalar, in for asynchronous form]
Size of data transfer.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>device_write_inband</strong> function writes a sequence of bytes to a device
object.  The meaning of <var>recnum</var> as well as the specific operation 
performed is device dependent.  This call differs from <strong>device_write</strong>
in that the bytes to be written are sent "inband" in the request IPC message.
<h3>RETURN VALUES</h3>
<p>
Only generic errors apply.
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="device_write.html"><strong>device_write</strong></a>,
<a href="device_reply_server.html"><strong>device_reply_server</strong></a>.