1 <h2>i386_io_port_add
</h2>
4 <strong>Function
</strong> - Permit target thread to invoke operations on the specified device.
7 <strong>kern_return_t i386_io_port_add
</strong>
8 <strong>(thread_act_t
</strong> <var>target_act
</var>,
9 <strong>device_t
</strong> <var>device
</var><strong>);
</strong>
14 <dt> <var>target_act
</var>
16 [in thread send right]
17 Thread whose permission bitmap is to be set.
19 <dt> <var>device
</var>
21 [in device send right]
22 The device to which I/O instructions are to be
27 The
<strong>i386_io_port_add
</strong> function adds a device to the
28 I/O permission bitmap for a
29 thread, thereby permitting the thread to execute I/O instructions against the
33 Normally, the thread must have called
<strong>i386_io_port_add
</strong>
34 for all devices to which it will execute I/O instructions. However, possessing
35 send rights to the
<var>iopl
</var> device port will cause the
36 <var>iopl
</var> device to be automatically added to the
37 thread's I/O map upon first attempted access. This is a backward
38 compatibility feature for the DOS emulator.
39 <h3>RETURN VALUES
</h3>
41 Only generic errors apply.
42 <h3>RELATED INFORMATION
</h3>
45 <a href=
"i386_io_port_list.html"><strong>i386_io_port_list
<strong></a>,
46 <a href=
"i386_io_port_remove.html"><strong>i386_io_port_remove
<strong></a>.