-<h2>device_read</h2>
\r<hr>
\r<p>
\r<strong>Function</strong> - Read a sequence of bytes from a specific device.
\r<h3>SYNOPSIS</h3>
\r<pre>
\r<strong>#include<device/device.h></strong>
\r\r<strong>kern_return_t device_read</strong>
\r <strong>(device_t</strong> <var>device</var>,
\r <strong>mach_port_t</strong> <var>reply_port</var>,
\r <strong>dev_mode_t</strong> <var>mode</var>,
\r <strong>recnum_t</strong> <var>recnum</var>,
\r <strong>io_buf_len_t</strong> <var>bytes_wanted</var>,
\r <strong>io_buf_ptr_t</strong> <var>io_buf_ptr_t</var>,
\r <strong>mach_msg_type_number_t</strong> <var>mach_msg_type_number_t</var><strong>);</strong>
\r\r\r<strong>#include<device/device_request.h></strong>
\r\r<strong>kern_return_t device_read_request</strong>
\r <strong>(mach_port_t</strong> <var>device</var>,
\r <strong>mach_port_t</strong> <var>reply_port</var>,
\r <strong>dev_mode_t</strong> <var>mode</var>,
\r <strong>recnum_t</strong> <var>recnum</var>,
\r <strong>io_buf_len_t</strong> <var>bytes_wanted</var><strong>);</strong>
\r\r\r\r<strong>kern_return_t ds_device_read_reply</strong>
\r <strong>(mach_port_t</strong> <var>reply_port</var>,
\r <strong>kern_return_t</strong> <var>return_code</var>,
\r <strong>io_buf_ptr_t</strong> <var>data</var>,
\r <strong>mach_msg_type_number_t</strong> <var>data_count</var><strong>);</strong>
\r</pre>
\r<h3>PARAMETERS</h3>
\r<dl>
\r<p>
\r<dt> <var>device</var>
\r<dd>
\r[in device send right]
\rA device port to the device to be read.
\r<p>
\r<dt> <var>reply_port</var>
\r<dd>
\r[in reply receive (to be converted to send-once) right]
\rThe port to
\rwhich the reply message is to be sent.
\r<p>
\r<dt> <var>mode</var>
\r<dd>
\r[in scalar]
\rI/O mode value. Meaningful options are:
\r<dl>
\r<p>
\r<dt> <strong>D_NOWAIT</strong>
\r<dd>
\rDo not wait if data is unavailable.
\r</dl>
\r<p>
\r<dt> <var>recnum</var>
\r<dd>
\r[in scalar]
\rRecord number to be read.
\r<p>
\r<dt> <var>bytes_wanted</var>
\r<dd>
\r[in scalar]
\rSize of data transfer.
\r<p>
\r<dt> <var>return_code</var>
\r<dd>
\r[in scalar]
\rThe return status code from the read.
\r<p>
\r<dt> <var>data</var>
\r<dd>
\r[out pointer to dynamic array of bytes, in for asynchronous form]
\rReturned data bytes.
\r<p>
\r<dt> <var>data_count</var>
\r<dd>
\r[out scalar, in for asynchronous form]
\rNumber of returned data bytes.
\r</dl>
\r<h3>DESCRIPTION</h3>
\r<p>
\rThe <strong>device_read</strong> function reads a sequence of bytes
\rfrom a device object. The
\rmeaning of <var>recnum</var> as well as the specific operation performed is device
\rdependent.
\r<h3>RETURN VALUES</h3>
\r<p>
\rOnly generic errors apply.
\r<h3>RELATED INFORMATION</h3>
\r<p>
\rFunctions:
\r<a href="device_read_inband.html"><strong>device_read_inband</strong></a>,
\r<a href="device_read_overwrite.html"><strong>device_read_overwrite</strong></a>,
\r<a href="device_reply_server.html"><strong>device_reply_server</strong></a>.
\r\ No newline at end of file
+<h2>device_read</h2>
+<hr>
+<p>
+<strong>Function</strong> - Read a sequence of bytes from a specific device.
+<h3>SYNOPSIS</h3>
+<pre>
+<strong>#include<device/device.h></strong>
+
+<strong>kern_return_t device_read</strong>
+ <strong>(device_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_len_t</strong> <var>bytes_wanted</var>,
+ <strong>io_buf_ptr_t</strong> <var>io_buf_ptr_t</var>,
+ <strong>mach_msg_type_number_t</strong> <var>mach_msg_type_number_t</var><strong>);</strong>
+
+
+<strong>#include<device/device_request.h></strong>
+
+<strong>kern_return_t device_read_request</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_len_t</strong> <var>bytes_wanted</var><strong>);</strong>
+
+
+
+<strong>kern_return_t ds_device_read_reply</strong>
+ <strong>(mach_port_t</strong> <var>reply_port</var>,
+ <strong>kern_return_t</strong> <var>return_code</var>,
+ <strong>io_buf_ptr_t</strong> <var>data</var>,
+ <strong>mach_msg_type_number_t</strong> <var>data_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 read.
+<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 if data is unavailable.
+</dl>
+<p>
+<dt> <var>recnum</var>
+<dd>
+[in scalar]
+Record number to be read.
+<p>
+<dt> <var>bytes_wanted</var>
+<dd>
+[in scalar]
+Size of data transfer.
+<p>
+<dt> <var>return_code</var>
+<dd>
+[in scalar]
+The return status code from the read.
+<p>
+<dt> <var>data</var>
+<dd>
+[out pointer to dynamic array of bytes, in for asynchronous form]
+Returned data bytes.
+<p>
+<dt> <var>data_count</var>
+<dd>
+[out scalar, in for asynchronous form]
+Number of returned data bytes.
+</dl>
+<h3>DESCRIPTION</h3>
+<p>
+The <strong>device_read</strong> function reads a sequence of bytes
+from a device object. The
+meaning of <var>recnum</var> as well as the specific operation performed is device
+dependent.
+<h3>RETURN VALUES</h3>
+<p>
+Only generic errors apply.
+<h3>RELATED INFORMATION</h3>
+<p>
+Functions:
+<a href="device_read_inband.html"><strong>device_read_inband</strong></a>,
+<a href="device_read_overwrite.html"><strong>device_read_overwrite</strong></a>,
+<a href="device_reply_server.html"><strong>device_reply_server</strong></a>.
projects / apple / xnu.git / blobdiff