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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="TheKeyboard.html" title="The Keyboard" /><link rel="prev" href="TheKeyboard_MoreOnKeyboardMapping.html" title="More On Keyboard Mapping" /><link rel="next" href="TheKeyboard_JourneyOfAKeystroke.html" title="Journey Of A Keystroke" /></head><body><div id="header"><div id="headerT"><div id="headerTL"><a accesskey="p" href="TheKeyboard_MoreOnKeyboardMapping.html" title="More On Keyboard Mapping"><img src="./images/navigation/prev.png" alt="Prev" /></a> <a accesskey="u" href="TheKeyboard.html" title="The Keyboard"><img src="./images/navigation/up.png" alt="Up" /></a> <a accesskey="n" href="TheKeyboard_JourneyOfAKeystroke.html" title="Journey Of A Keystroke"><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 - Special Topics - The Keyboard</div></div><div id="headerB">Prev: <a href="TheKeyboard_MoreOnKeyboardMapping.html">More On Keyboard Mapping</a>  Up: <a href="TheKeyboard.html">The Keyboard</a>  Next: <a href="TheKeyboard_JourneyOfAKeystroke.html">Journey Of A Keystroke</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="TheKeyboard_CharacterConstants"></a>Character Constants</h2></div></div></div><p>The Interface Kit defines constants for characters that aren't normally
represented by a visible symbol. This includes the usual space and
backspace characters, but most invisible characters are produced by the
function keys and the navigation keys located between the main keyboard
and the numeric keypad. The character values associated with these keys
are more or less arbitrary, so you should always use the constant in your
code rather than the actual character value. Many of these characters are
also produced by alphabetic keys when a <span class="keycap">Control</span> key is held down.</p><p>The table below lists character constants defined in the kit and the keys
they're associated with.</p><div class="informaltable"><table border="1"><colgroup><col /><col /><col /></colgroup><thead><tr><th>Key label</th><th>Key code</th><th>Character reported</th></tr></thead><tbody><tr><td>Backspace</td><td>0x1e</td><td><code class="constant">B_BACKSPACE</code></td></tr><tr><td>Tab</td><td>0x26</td><td><code class="constant">B_TAB</code></td></tr><tr><td>Enter</td><td>0x47</td><td><code class="constant">B_ENTER</code></td></tr><tr><td>space bar</td><td>0x5e</td><td><code class="constant">B_SPACE</code></td></tr><tr><td>Escape</td><td>0x01</td><td><code class="constant">B_ESCAPE</code></td></tr><tr><td>F1–F12 0x02 through</td><td>0x0d</td><td><code class="constant">B_FUNCTION_KEY</code></td></tr><tr><td>Print Screen</td><td>0x0e</td><td><code class="constant">B_FUNCTION_KEY</code></td></tr><tr><td>Scroll Lock</td><td>0x0f</td><td><code class="constant">B_FUNCTION_KEY</code></td></tr><tr><td>Pause</td><td>0x10</td><td><code class="constant">B_FUNCTION_KEY</code></td></tr><tr><td>System Request</td><td>0x7e</td><td>0xc8</td></tr><tr><td>Break</td><td>0x7f</td><td>0xca</td></tr><tr><td>Insert</td><td>0x1f</td><td><code class="constant">B_INSERT</code></td></tr><tr><td>Home</td><td>0x20</td><td><code class="constant">B_HOME</code></td></tr><tr><td>Page Up</td><td>0x21</td><td><code class="constant">B_PAGE_UP</code></td></tr><tr><td>Delete</td><td>0x34</td><td><code class="constant">B_DELETE</code></td></tr><tr><td>End</td><td>0x35</td><td><code class="constant">B_END</code></td></tr><tr><td>Page Down</td><td>0x36</td><td><code class="constant">B_PAGE_DOWN</code></td></tr><tr><td>up arrow</td><td>0x57</td><td><code class="constant">B_UP_ARROW</code></td></tr><tr><td>left arrow</td><td>0x61</td><td><code class="constant">B_LEFT_ARROW</code></td></tr><tr><td>down arrow</td><td>0x62</td><td><code class="constant">B_DOWN_ARROW</code></td></tr><tr><td>right arrow</td><td>0x63</td><td><code class="constant">B_RIGHT_ARROW</code></td></tr></tbody></table></div><p>Several keys are mapped to the <code class="constant">B_FUNCTION_KEY</code> character. An application
can determine which function key was pressed to produce the character by
testing the key code against these constants:</p><div class="informaltable"><table border="1"><colgroup><col /><col /><col /></colgroup><tbody><tr><td><code class="constant">B_F1_KEY</code></td><td><code class="constant">B_F6_KEY</code></td><td><code class="constant">B_F11_KEY</code></td></tr><tr><td><code class="constant">B_F2_KEY</code></td><td><code class="constant">B_F7_KEY</code></td><td><code class="constant">B_F12_KEY</code></td></tr><tr><td><code class="constant">B_F3_KEY</code></td><td><code class="constant">B_F8_KEY</code></td><td><code class="constant">B_PRINT_KEY</code> (the "Print Screen" key)</td></tr><tr><td><code class="constant">B_F4_KEY</code></td><td><code class="constant">B_F9_KEY</code></td><td><code class="constant">B_SCROLL_KEY</code> (the "Scroll Lock" key)</td></tr><tr><td><code class="constant">B_F5_KEY</code></td><td><code class="constant">B_F10_KEY</code></td><td><code class="constant">B_PAUSE_KEY</code></td></tr></tbody></table></div><p>Note that key 0x30 <span class="keycap">P</span> is also mapped to
<code class="constant">B_FUNCTION_KEY</code> when the <span class="keycap">Control</span>
key is held down.</p><p>Each of the character constants listed above is a one-byte value falling
in the range of values where <acronym class="acronym">ASCII</acronym> and
<span class="trademark">Unicode</span>™ overlap. For convenience,
the Interface Kit also defines some constants for common characters that
fall outside that range. These characters have multibyte representations
in <acronym class="acronym">UTF-8</acronym>, so the constant is defined as a character string. For example:</p><pre class="programlisting example cpp">#define <code class="constant">B_UTF8_OPEN_QUOTE</code>  "xE2x80x9C"
#define <code class="constant">B_UTF8_CLOSE_QUOTE</code> "xE2x80x9D"
#define <code class="constant">B_UTF8_COPYRIGHT</code>   "xC2xA9"</pre><p>See "<a class="xref" href="TheInterfaceKit_GeneralConstants.html#Constants_Character" title="Character Constants">Character Constants</a>" in the
"<a class="xref" href="TheInterfaceKit_GeneralConstants.html" title="General Constants">General Constants</a>"
section of The Interface Kit for a full list of these
constants.</p></div><div id="footer"><hr /><div id="footerT">Prev: <a href="TheKeyboard_MoreOnKeyboardMapping.html">More On Keyboard Mapping</a>  Up: <a href="TheKeyboard.html">The Keyboard</a>  Next: <a href="TheKeyboard_JourneyOfAKeystroke.html">Journey Of A Keystroke</a> </div><div id="footerB"><div id="footerBL"><a href="TheKeyboard_MoreOnKeyboardMapping.html" title="More On Keyboard Mapping"><img src="./images/navigation/prev.png" alt="Prev" /></a> <a href="TheKeyboard.html" title="The Keyboard"><img src="./images/navigation/up.png" alt="Up" /></a> <a href="TheKeyboard_JourneyOfAKeystroke.html" title="Journey Of A Keystroke"><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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