Karabiner private.xml for volume and music playback controls using F13 - F19 keys on wired Apple Keyboard

private.xml

<?xml version="1.0"?>
<root>
  <item>
    <name>F19 to Sleep</name>
    <identifier>Sleep</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F19,
        KeyCode::VK_CONSUMERKEY_EJECT, ModifierFlag::OPTION_L | ModifierFlag::COMMAND_L
    </autogen>
 </item>
 <item>
    <name>F18 to Volume Up</name>
    <identifier>VolumeUp</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F18,
        ConsumerKeyCode::VOLUME_UP
    </autogen>
 </item>
 <item>
    <name>F17 to Volume Down</name>
    <identifier>VolumeDown</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F17,
        ConsumerKeyCode::VOLUME_DOWN
    </autogen>
 </item>
 <item>
    <name>F16 to Mute</name>
    <identifier>VolumeMute</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F16,
        ConsumerKeyCode::VOLUME_MUTE
    </autogen>
 </item>
 <item>
    <name>F15 to Next Song</name>
    <identifier>NextSong</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F15,
        KeyCode::VK_CONSUMERKEY_MUSIC_NEXT
    </autogen>
 </item>
 <item>
    <name>F14 to Play/Pause Song</name>
    <identifier>PlayPauseSong</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F14,
        KeyCode::VK_CONSUMERKEY_MUSIC_PLAY
    </autogen>
 </item>
 <item>
    <name>F13 to Previous Song</name>
    <identifier>PrevSong</identifier>
    <autogen>
        __KeyToKey__
        KeyCode::F13,
        KeyCode::VK_CONSUMERKEY_MUSIC_PREV
    </autogen>
 </item>
 <vkopenurldef>
   <name>KeyCode::VK_OPEN_URL_SHELL_display_sleep</name>
   <url type="shell">open -a /System/Library/Frameworks/ScreenSaver.framework/Versions/A/Resources/ScreenSaverEngine.app</url>
 </vkopenurldef>
 <item>
    <name>Eject to Start Screensaver</name>
    <identifier>EjectStartScreensaver</identifier>
    <autogen>
    __KeyToKey__ ConsumerKeyCode::EJECT, ModifierFlag::NONE, 
    KeyCode::VK_OPEN_URL_SHELL_display_sleep
    </autogen>
 </item>
</root>

Hotkeys

1. F13 - Previous Song
2. F14 - Play / Pause Song
3. F15 - Next Song
4. F16 - Mute
5. F17 - Volume Down
6. F18 - Volume Up
7. F19 - Sleep (bonus)
8. Eject - Lock & Screensaver (bonus)

Reference

• https://github.com/tekezo/Karabiner/blob/master/src/core/server/Resources/include/checkbox/standards/fn.xml
• http://osxnotes.net/karabiner.html