osfmk/man/device_write.html

   1 <h2>device_write</h2>
   2 <hr>
   3 <p>
   4 <strong>Function</strong> - Write a sequence of bytes to a specific device.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>#include&ltdevice/device.h&gt</strong>
   8
   9 <strong>kern_return_t   device_write</strong>
  10                 <strong>(device_t</strong>                                <var>device</var>,
  11                  <strong>mach_port_t</strong>                         <var>reply_port</var>,
  12                  <strong>dev_mode_t</strong>                                <var>mode</var>,
  13                  <strong>recnum_t</strong>                                <var>recnum</var>,
  14                  <strong>io_buf_ptr_t</strong>                              <var>data</var>,
  15                  <strong>mach_msg_type_number_t</strong>              <var>data_count</var>,
  16                  <strong>io_buf_len_t</strong>                      <var>io_buf_len_t</var><strong>);</strong>
  17
  18
  19 <strong>#include&ltdevice/device_request.h&gt</strong>
  20
  21 <strong>kern_return_t   device_write_request</strong>
  22                 <strong>(mach_port_t</strong>                             <var>device</var>,
  23                  <strong>mach_port_t</strong>                         <var>reply_port</var>,
  24                  <strong>dev_mode_t</strong>                                <var>mode</var>,
  25                  <strong>recnum_t</strong>                                <var>recnum</var>,
  26                  <strong>io_buf_ptr_t</strong>                              <var>data</var>,
  27                  <strong>mach_msg_type_number_t</strong>              <var>data_count</var><strong>);</strong>
  28
  29
  30 <strong>kern_return_t   ds_device_write_reply</strong>
  31                 <strong>(mach_port_t</strong>                         <var>reply_port</var>,
  32                  <strong>kern_return_t</strong>                      <var>return_code</var>,
  33                  <strong>io_buf_len_t</strong>                     <var>bytes_written</var><strong>);</strong>
  34 </pre>
  35 <h3>PARAMETERS</h3>
  36 <dl>
  37 <p>
  38 <dt> <var>device</var>
  39 <dd>
  40 [in device send right]
  41 A device port to the device to be written.
  42 <p>
  43 <dt> <var>reply_port</var>
  44 <dd>
  45 [in reply receive (to be converted to send-once) right]
  46 The port to
  47 which the reply message is to be sent.
  48 <p>
  49 <dt> <var>mode</var>
  50 <dd>
  51 [in scalar]
  52 I/O mode value.  Meaningful options are:
  53 <dl>
  54 <p>
  55 <dt> <strong>D_NOWAIT</strong>
  56 <dd>
  57 Do not wait for I/O completion.
  58 </dl>
  59 <p>
  60 <dt> <var>recnum</var>
  61 <dd>
  62 [in scalar]
  63 Record number to be written.
  64 <p>
  65 <dt> <var>data</var>
  66 <dd>
  67 [pointer to in array of bytes]
  68 Data bytes to be written.
  69 <p>
  70 <dt> <var>data_count</var>
  71 <dd>
  72 [in scalar]
  73 Number of data bytes to be written.
  74 <p>
  75 <dt> <var>return_code</var>
  76 <dd>
  77 [in scalar]
  78 The return status code from the write.
  79 <p>
  80 <dt> <var>bytes_written</var>
  81 <dd>
  82 [out scalar, in for asynchronous form]
  83 Size of data transfer.
  84 </dl>
  85 <h3>DESCRIPTION</h3>
  86 <p>
  87 The <strong>device_write</strong> function writes a sequence of bytes
  88 to a device object.  The
  89 meaning of <var>recnum</var> as well as the specific operation performed is device
  90 dependent.
  91 <h3>RETURN VALUES</h3>
  92 <p>
  93 Only generic errors apply.
  94 <h3>RELATED INFORMATION</h3>
  95 <p>
  96 Functions:
  97 <a href="device_write_inband.html"><strong>device_write_inband</strong></a>,
  98 <a href="device_reply_server.html"><strong>device_reply_server</strong></a>.