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    <![endif]--><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /><meta name="keywords" content="Access, BeOS, BeBook, API" /><link rel="start" href="index.html" title="The Be Book" /><link rel="up" href="TheInputServer_Overview.html" title="The Input Server" /><link rel="prev" href="TheInputServer_Overview.html" title="The Input Server" /><link rel="next" href="BInputDevice_Overview.html" title="BInputDevice" /></head><body><div id="header"><div id="headerT"><div id="headerTL"><a accesskey="p" href="TheInputServer_Overview.html" title="The Input Server"><img src="./images/navigation/prev.png" alt="Prev" /></a> <a accesskey="u" href="TheInputServer_Overview.html" title="The Input Server"><img src="./images/navigation/up.png" alt="Up" /></a> <a accesskey="n" href="BInputDevice_Overview.html" title="BInputDevice"><img src="./images/navigation/next.png" alt="Next" /></a></div><div id="headerTR"><div id="navigpeople"><a href="http://www.haiku-os.org"><img src="./images/People_24.png" alt="haiku-os.org" title="Visit The Haiku Website" /></a></div><div class="navighome" title="Home"><a accesskey="h" href="index.html"><img src="./images/navigation/home.png" alt="Home" /></a></div><div class="navigboxed" id="navigindex"><a accesskey="i" href="ClassIndex.html" title="Index">I</a></div><div class="navigboxed" id="naviglang" title="English">en</div></div><div id="headerTC">The Be Book - System Overview - The Input Server</div></div><div id="headerB">Prev: <a href="TheInputServer_Overview.html">The Input Server</a>  Up: <a href="TheInputServer_Overview.html">The Input Server</a>  Next: <a href="BInputDevice_Overview.html">BInputDevice</a></div><hr /></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h2 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction"></a>Introduction</h2></div></div></div><p>The Input Server is a system service that accepts user events (on the
mouse and keyboard, typically) at one end, and dispatches them to the App
Server at the other. In between, the Input Server runs the events through
a series of filters that can inspect and modify them. The generation and
filtering of events is performed by the add-ons that the Input Server
loads; the Server itself just provides the plumbing. Event-generating
add-ons (called input devices) typically correspond to one or more device
drivers, although this isn't a requirement. An event-filtering add-on
(input filter) processes the events that are fed to it; input filters
aren't intended to correspond to hardware. A third type of Input Server
add-on—an input method—is used to implement input method
mechanisms, which convert keyboard events into character sets that can't
be easily represented on a standard keyboard, such as Kanji.</p><p>Each of these add-on types (input devices, filters, and methods) is
represented by a C++ class:
<a class="link" href="BInputServerDevice.html" title="BInputServerDevice"><code class="classname">BInputServerDevice</code></a>,
<a class="link" href="BInputServerFilter.html" title="BInputServerFilter"><code class="classname">BInputServerFilter</code></a>, and
<a class="link" href="BInputServerMethod.html" title="BInputServerMethod"><code class="classname">BInputServerMethod</code></a>.
For each add-on you want to create, you subclass the
appropriate class and override its hook functions. An additional
class—<a class="link" href="BInputDevice.html" title="BInputDevice"><code class="classname">BInputDevice</code></a>—lets
a "normal" application send messages
back through the Input Server to the input devices; a
<a class="link" href="BInputDevice.html" title="BInputDevice"><code class="classname">BInputDevice</code></a> object
can be useful if you're creating a preference app for a custom Input
Server add-on, for example.</p><p>A map of the Input Server world looks like this:</p><div class="mediaobject"><img src="./images/TheInputServer/input_server_map.png" alt="Input Server Map" /></div><p>Note that the Input Server and its add-ons (and
<a class="link" href="BInputDevice.html" title="BInputDevice"><code class="classname">BInputDevice</code></a>) all live in
user space, so, in theory, there's nothing that a "normal" application
can do that an Input Server add-on can't do. However, Input Server
add-ons are loaded early in the boot process, before some system services
(such as the Media and Network servers) have started. Attempting to use
services from these servers before they've started is a good way to wedge
the system.</p><p>The BeOS provides a few Input Server add-ons: It installs input devices
that handle a variety of mice and keyboard drivers, and an input filter
that the Screen Saver engine uses to detect user activity (on the mouse
and keyboard). BeOS's only built-in input method is installed when you
choose the Japanese language option during the installation process.</p><p>Currently, events that are generated by the BeOS joystick drivers do
not go through the Input Server.</p><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><hr /><div xmlns:d="http://docbook.org/ns/docbook"><h3 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Drivers_Input_Devices"></a>Drivers and Input Devices</h3></div></div></div><p>As mentioned above, most input devices (i.e. input-generating add-ons)
correspond to one or more device drivers. For example, the BeOS mouse
input device manages all the mouse drivers that the OS provides.</p><p>It's important to keep in mind that an input device is not the same as
the device driver(s) it manages—they're separate pieces of code
that execute in separate address spaces: the drivers run in the kernel,
the add-ons run in the Input Server. An input device can open() a driver,
but it must not explicitly load the driver. In other words, the add-on
shouldn't re-invent or subvert the kernel's driver-loading mechanism.</p><p>Similar to drivers, Input Server add-ons must be scrupulous about
managing their memory and threads:</p><ul class="itemizedlist"><li><p>Memory that an add-on allocates must be freed when the add-on is
unloaded, otherwise the add-on will leak.</p></li><li><p>The hook functions that are invoked on your add-on are executed in
threads that must stay as "live" as possible. If your add-on does a lot
of processing that can be performed asynchronously—for example,
if it's an input device that's "watching" a piece of hardware—the
add-on should spawn a thread.</p></li></ul><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Building"></a>Building</h4></div></div></div><p>Like all add-ons, Input Server add-ons are compiled as shared libraries.
The add-ons must link against input_server, renamed (as a symbolic link)
to <code class="filename">_APP_</code>. In other words, you set up a symbolic link like this:</p><pre class="screen">$ cd &lt;yourProjectDirectory&gt;
$ ln -s /boot/beos/system/servers/input_server _APP_</pre><p>And then link against <code class="filename">_APP_</code>.</p></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Installing"></a>Installing</h4></div></div></div><p>The input server looks for add-ons in the
<code class="filename">input_server</code> directory within
<code class="constant">B_BEOS_ADDONS_DIRECTORY</code>, <code class="constant">B_COMMON_ADDONS_DIRECTORY</code>, and
<code class="constant">B_USER_ADDONS_DIRECTORY</code>. Where you install your add-ons depends on what
type of add-on it is:</p><ul class="itemizedlist"><li><p><code class="filename">input_server/devices</code> is for input devices</p></li><li><p><code class="filename">input_server/filters</code> is for input filters</p></li><li><p><code class="filename">input_server/methods</code> is for input methods</p></li><li><p>You can install your input devices in the latter two
directories—i.e. those under <code class="constant">B_COMMON_ADDONS_DIRECTORY</code>, and
<code class="constant">B_USER_ADDONS_DIRECTORY</code>.</p></li><li><p>The <code class="constant">B_BEOS_ADDONS_DIRECTORY</code> is reserved for add-ons that are supplied
by the BeOS.</p></li></ul></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Loading"></a>Loading</h4></div></div></div><p>The Input Server automatically loads (or attempts to load) all add-ons at
boot time.</p><p>Currently, the Input Server doesn't dynamically load add-ons. This is a
particular annoyance if you're developing and testing an add-on. To work
around this lack, move your add-on into the appropriate directory, and
then quit and restart the Input Server from a Terminal:</p><pre class="screen">/system/servers/input_server -q</pre><p>This will gracefully shutdown the Input Server and then re-launch it. The
first thing the Server does when it comes back up is re-load the add-ons
from its add-on directories.</p><p>Your mouse and keyboard (and other input devices) will go dead for a
moment while this is happening. This is normal.</p></div></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><hr /><div xmlns:d="http://docbook.org/ns/docbook"><h3 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Input_Server_You"></a>Input Server and You</h3></div></div></div><p>The Input Server gives applications a chance to take advantage of useful
features present in input devices more interesting than your typical
101-key keyboard and 3-button mouse.</p><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Mice_Tablets"></a>Mice and Tablets</h4></div></div></div><p>The Input Server extends the plain <code class="constant">B_MOUSE_MOVED</code> message (which triggers
a <a class="link" href="BView.html" title="BView"><code class="classname">BView</code></a>'s
<a class="link" href="BView.html#BView_MouseMoved" title="MouseMoved()"><code class="methodname">MouseMoved()</code></a>
function) beyond its ordinary existence to let
things like tablets pass along extra information about a user's actions.
For example, drawing tablets can track the user's movement with greater
precision than a mouse, and can include drawing pressure and tilt
information. Some also include an "eraser."</p><p>If an application can do something useful with this information (and
let's face it; drawing applications that respond to pressure and tilt on
a drawing pad are useful as well as being cool), it'll be present in the
<code class="constant">B_MOUSE_MOVED</code> message:</p><pre class="programlisting example cpp"><span class="type">void</span> <code class="classname">MyView</code>::<code class="methodname">MouseMoved</code>(<span class="type">BPoint *</span><code class="parameter">where</code>,
                         <span class="type">uint32</span> <code class="parameter">transit</code>, <span class="type">BMessage *</span><code class="parameter">drag_msg</code>)
{
   <span class="type">BMessage *</span><code class="varname">moved_msg</code> = <code class="methodname">Window</code>()-&gt;<code class="methodname">CurrentMessage</code>();
   ...
}</pre><p>The extra information that a "mouse" input device could add to the
<code class="constant">B_MOUSE_MOVED</code> messages includes:</p><ul class="itemizedlist"><li><p>more precise position information</p></li><li><p>drawing pressure</p></li><li><p>pen tilt</p></li><li><p>"eraser" mode</p></li></ul></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Precision_Position_Information"></a>Precision Position Information</h4></div></div></div><p>Tablets store the absolute position of the pointer with as much precision
as they can in the <code class="varname">be:tablet_x</code> and
<code class="varname">be:tablet_y</code> fields:</p><pre class="programlisting example cpp"><span class="type">float</span> <code class="varname">x</code>, <code class="varname">y</code>;
<code class="varname">x</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindFloat</code>( "be:tablet_x" );
<code class="varname">y</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindFloat</code>( "be:tablet_y" );</pre><p>These entries will be scaled to the range [0.0 to 1.0].</p></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Pressure"></a>Pressure</h4></div></div></div><p>Tablet pressure is stored as a float in the range [0.0 to 1.0] (minimum
to maximum), present in the <code class="varname">be:tablet_pressure</code> field:</p><pre class="programlisting example cpp"><span class="type">float</span> <code class="varname">pressure</code>;
<code class="varname">pressure</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindFloat</code>( "be:tablet_pressure" );</pre></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Tilt"></a>Tilt</h4></div></div></div><p>Pen tilt is expressed as a pair of <span class="type">float</span>s in the range [0.0 to 1.0],
where (-1.0, -1.0) tilts to the left-top, (1.0, 1.0) tilts to the
right-bottom, and (0.0, 0.0) is no tilt. These <span class="type">float</span>s are found in the
<code class="varname">be:tablet_tilt_x</code> and <code class="varname">be:tablet_tilt_y</code> fields:</p><pre class="programlisting example cpp"><span class="type">float</span> <code class="varname">tilt_x</code>, <code class="varname">tilt_y</code>;
<code class="varname">tilt_x</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindFloat</code>( "be:tablet_tilt_x" );
<code class="varname">tilt_y</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindFloat</code>( "be:tablet_tilt_y" );</pre></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Eraser_Mode"></a>Eraser Mode</h4></div></div></div><p>The pen's eraser mode is expressed as an <span class="type">int32</span>
in the <code class="varname">be:tablet_eraser</code>
field:</p><pre class="programlisting example cpp"><span class="type">int32</span> <code class="varname">erase_mode</code>;
<code class="varname">erase_mode</code> = <code class="varname">moved_msg</code>-&gt;<code class="methodname">FindInt32</code>( "be:tablet_eraser" );</pre><p>A value of 1 means the pen is reversed (i.e. the eraser is on) and 0
means the pen is behaving normally. Other eraser modes may be defined in
the future.</p></div></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><hr /><div xmlns:d="http://docbook.org/ns/docbook"><h3 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Supporting_Input_Methods_In_Views"></a>Supporting Input Methods in Views</h3></div></div></div><p>When the user is entering text using an input method, such as the
Japanese language input method that became an installation option in R4,
there are two ways that applications can handle their input:</p><div class="orderedlist"><ol><li><p>in-line: the text entry interface object lets them enter text directly</p></li><li><p>bottom-line: the input method itself pops up a window to accept the
user's input, and then passes <code class="constant">B_KEY_DOWN</code> messages simulating the
characters to the application; the app doesn't have to do anything to
support bottom-line input</p></li></ol></div><p>If your application's text-entry needs are met by the Interface Kit's
<a class="link" href="BTextControl.html" title="BTextControl"><code class="classname">BTextControl</code></a> and
<a class="link" href="BTextView.html" title="BTextView"><code class="classname">BTextView</code></a>
objects, it'll automatically use the in-line
mode, which gives the user a much better experience. If you're writing
your own text widget, you'll have to do a little work to let the user
input text directly.</p><p>Doing this is a very good idea; making your application behave well when
dealing with foreign (to you) languages will improve your application's
acceptance around the world.</p><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><div xmlns:d="http://docbook.org/ns/docbook"><h4 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="TheInputServer_Introduction_Messages_From_Input_Methods"></a>Messages from Input Methods</h4></div></div></div><p>When interacting with an input method, your view's
<a class="link" href="BView.html#BView_MessageReceived" title="MessageReceived()"><code class="methodname">MessageReceived()</code></a>
function will receive <code class="constant">B_INPUT_METHOD_EVENT</code> messages; inside is a
<code class="varname">be:opcode</code> field (an <span class="type">int32</span> value) indicating
the kind of event:</p><table class="variablelist constants"><thead><tr><th>Constant</th><th>Description</th></tr></thead><tbody><tr><td><p><span class="term"><code class="constant">B_INPUT_METHOD_STARTED</code></span></p></td><td><p>Tells your view that a new input transaction has
begun. Inside the message is a
<a class="link" href="BMessenger.html" title="BMessenger"><code class="classname">BMessenger</code></a>
named <code class="varname">be:reply_to</code>; you should
store this because it's your only way of talking to the input method
while the transaction is going on.</p></td></tr><tr><td><p><span class="term"><code class="constant">B_INPUT_METHOD_STOPPED</code></span></p></td><td><p>Lets you know the
transaction is over; you should discard the <a class="link" href="BMessenger.html" title="BMessenger"><code class="classname">BMessenger</code></a> at this point
because it's gone stale.</p></td></tr></tbody></table><p>In between the <code class="constant">B_INPUT_METHOD_STARTED</code> and
<code class="constant">B_INPUT_METHOD_STOPPED</code>
messages, you'll receive various <code class="constant">B_INPUT_METHOD_CHANGED</code> and
<code class="constant">B_INPUT_METHOD_LOCATION_REQUEST</code> messages as the transaction proceeds.</p><p><code class="constant">B_INPUT_METHOD_CHANGED</code>
does most of the work in an input transaction; its
message contains the following important fields:</p><div class="informaltable"><table border="1"><colgroup><col /><col /><col /></colgroup><thead><tr><th>Entry</th><th>Type</th><th>Description</th></tr></thead><tbody><tr><td><code class="varname">be:string</code></td><td><code class="constant">B_STRING_TYPE</code></td><td>The text the user is currently entering; display
it at the insertion point.
<a class="link" href="BTextView.html" title="BTextView"><code class="classname">BTextView</code></a>
also highlights the text in blue to
show that it's part of a transitory transaction.</td></tr><tr><td><code class="varname">be:selection</code></td><td><code class="constant">B_INT32_TYPE</code></td><td>A pair of <code class="constant">B_INT32_TYPE</code> offsets into the
<code class="varname">be:string</code> if any of the text <code class="varname">be:string</code>
is currently selected by the user.
<a class="link" href="BTextView.html" title="BTextView"><code class="classname">BTextView</code></a>
highlights this selection in red instead of drawing it in blue.</td></tr><tr><td><code class="varname">be:clause_start</code></td><td><code class="constant">B_INT32_TYPE</code></td><td>Zero or more offsets into the <code class="varname">be:string</code> for
handling languages (such as Japanese) that separate a sentence or phrase
into numerous clauses. An equal number of <code class="varname">be:clause_start</code> and
<code class="varname">be:clause_end</code> pairs delimit these clauses;
<a class="link" href="BTextView.html" title="BTextView"><code class="classname">BTextView</code></a>
separates the blue/red highlighting wherever there is a clause boundary.</td></tr><tr><td><code class="varname">be:clause_end</code></td><td><code class="constant">B_INT32_TYPE</code></td><td>Zero or more offsets into <code class="varname">be:string</code>; there
will be as many <code class="varname">be:clause_end</code> entries as there
are <code class="varname">be:clause_start</code>.</td></tr><tr><td><code class="varname">be:confirmed</code></td><td><code class="constant">B_BOOL_TYPE</code></td><td>True when the user has entered and "confirmed"
the current string and wishes to end the transaction.
<a class="link" href="BTextView.html" title="BTextView"><code class="classname">BTextView</code></a>
unhighlights the blue/red text and waits for a <code class="constant">B_INPUT_METHOD_STOPPED</code> (to
close the transaction) or another <code class="constant">B_INPUT_METHOD_CHANGED</code> (to start a new
transaction immediately).</td></tr></tbody></table></div><p><code class="constant">B_INPUT_METHOD_LOCATION_REQUEST</code>
is the input method's way of asking you for the on-screen location
of each character in your representation of the
<code class="varname">be:string</code>. This information
can be used by the input method to pop up additional windows giving the
user an opportunity to select characters from a list or anything else that
makes sense. When you get a
<code class="constant">B_INPUT_METHOD_LOCATION_REQUEST</code>, reply to the
<code class="varname">be:reply_to</code> messenger (that you saved from the
<code class="constant">B_INPUT_METHOD_STARTED</code> message) with a
<code class="constant">B_INPUT_METHOD_EVENT</code> message, filling in the following
fields:</p><div class="informaltable"><table border="1"><colgroup><col /><col /><col /></colgroup><thead><tr><th>Entry</th><th>Type</th><th>Description</th></tr></thead><tbody><tr><td><code class="varname">be:opcode</code></td><td><code class="constant">B_INT32_TYPE</code></td><td>Use <code class="constant">B_INPUT_METHOD_LOCATION_REQUEST</code> for the opcode.</td></tr><tr><td><code class="varname">be:location_reply</code></td><td><code class="constant">B_POINT_TYPE</code></td><td>The co-ordinates of each character (there
should be one <code class="varname">be:location_reply</code> for every
character in <code class="varname">be:string</code> in
screen co-ordinates not view or window co-ordinates).</td></tr><tr><td><code class="varname">be:height_reply</code></td><td><code class="constant">B_FLOAT_TYPE</code></td><td>The height of each character in <code class="varname">be:string</code>.</td></tr></tbody></table></div></div></div><div class="section"><div xmlns="" xmlns:d="http://docbook.org/ns/docbook" class="titlepage"><div><hr /><div xmlns:d="http://docbook.org/ns/docbook"><h3 xmlns="http://www.w3.org/1999/xhtml" class="title"><a id="id532349"></a>App and Input Events</h3></div></div></div><p>If you're writing an application and want to record or react to input
events without writing an Input Server add-on (which, of course, requires
an Input Server restart), you can:</p><div class="orderedlist"><ol><li><p>Create a window off-screen, at a co-ordinate like (-10.0, -10.0).</p></li><li><p>Add a view to the window at (0.0, 0.0).</p></li><li><p><a class="link" href="BWindow.html#BWindow_Show" title="Show(), Hide(), IsHidden(), Minimize(), IsMinimized()"><code class="methodname">Show()</code></a>
and then
<a class="link" href="BWindow.html#BWindow_Hide"><code class="methodname">Hide()</code></a>
the window; this is necessary or the App
Server won't send you any messages.</p></li><li><p>Move the hidden window to (0.0, 0.0).</p></li><li><p>Implement the window's
<a class="link" href="BWindow.html#BWindow_DispatchMessage" title="DispatchMessage()"><code class="methodname">DispatchMessage()</code></a>
function to handle
<code class="constant">B_KEY_DOWN</code>, <code class="constant">B_MOUSE_UP</code>, or
whatever other input events you're interested
in observing.</p></li></ol></div><p>Modifying these messages won't affect any other applications in the
system; by the time they reach your application, they've already passed
through the Input Server.</p><p>You can see this trick in action in Doug Fulton's masterful Whistle
application (found at ftp://ftp.be.com/pub/samples/midi_kit/Whistle.zip).</p></div></div><div id="footer"><hr /><div id="footerT">Prev: <a href="TheInputServer_Overview.html">The Input Server</a>  Up: <a href="TheInputServer_Overview.html">The Input Server</a>  Next: <a href="BInputDevice_Overview.html">BInputDevice</a> </div><div id="footerB"><div id="footerBL"><a href="TheInputServer_Overview.html" title="The Input Server"><img src="./images/navigation/prev.png" alt="Prev" /></a> <a href="TheInputServer_Overview.html" title="The Input Server"><img src="./images/navigation/up.png" alt="Up" /></a> <a href="BInputDevice_Overview.html" title="BInputDevice"><img src="./images/navigation/next.png" alt="Next" /></a></div><div id="footerBR"><div><a href="http://www.haiku-os.org"><img src="./images/People_24.png" alt="haiku-os.org" title="Visit The Haiku Website" /></a></div><div class="navighome" title="Home"><a accesskey="h" href="index.html"><img src="./images/navigation/home.png" alt="Home" /></a></div></div><div id="footerBC"><a href="http://www.access-company.com/home.html" title="ACCESS Co."><img alt="Access Company" src="./images/access_logo.png" /></a></div></div></div><div id="licenseFooter"><div id="licenseFooterBL"><a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/" title="Creative Commons License"><img alt="Creative Commons License" style="border-width:0" src="https://licensebuttons.net/l/by-nc-nd/3.0/88x31.png" /></a></div><div id="licenseFooterBR"><a href="./LegalNotice.html">Legal Notice</a></div><div id="licenseFooterBC"><span id="licenseText">This work is licensed under a
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