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<p>The <code>getevent</code> tool runs on the device and provides information
about input devices and a live dump of kernel input events.</p>
<p>This tool is useful for ensuring device drivers are reporting the
expected set of capabilities for each input device and are generating the
desired stream of input events.</p>

<h2 id="showing-device-capabilities">Showing device capabilities</h2>
<p>Use the <code>-p</code> option with the <code>adb</code> command to see all of the keys and axes a device
reports.</p>

<pre class="devsite-terminal devsite-click-to-copy">adb shell su -- getevent -p</pre>

<p>The following example lists the Linux key codes and other events a
particular keyboard says it supports.</p>

<pre>
  name:     "Motorola Bluetooth Wireless Keyboard"
  events:
    KEY (0001): 0001  0002  0003  0004  0005  0006  0007  0008
                0009  000a  000b  000c  000d  000e  000f  0010
                0011  0012  0013  0014  0015  0016  0017  0018
                0019  001a  001b  001c  001d  001e  001f  0020
                0021  0022  0023  0024  0025  0026  0027  0028
                0029  002a  002b  002c  002d  002e  002f  0030
                0031  0032  0033  0034  0035  0036  0037  0038
                0039  003a  003b  003c  003d  003e  003f  0040
                0041  0042  0043  0044  0045  0046  0047  0048
                0049  004a  004b  004c  004d  004e  004f  0050
                0051  0052  0053  0055  0056  0057  0058  0059
                005a  005b  005c  005d  005e  005f  0060  0061
                0062  0063  0064  0066  0067  0068  0069  006a
                006b  006c  006d  006e  006f  0071  0072  0073
                0074  0075  0077  0079  007a  007b  007c  007d
                007e  007f  0080  0081  0082  0083  0084  0085
                0086  0087  0088  0089  008a  008c  008e  0090
                0096  0098  009b  009c  009e  009f  00a1  00a3
                00a4  00a5  00a6  00ab  00ac  00ad  00b0  00b1
                00b2  00b3  00b4  00b7  00b8  00b9  00ba  00bb
                00bc  00bd  00be  00bf  00c0  00c1  00c2  00d9
                00f0  0110  0111  0112  01ba
    REL (0002): 0000  0001  0008
    ABS (0003): 0028  : value 223, min 0, max 255, fuzz 0, flat 0, resolution 0
                0029  : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0
                002a  : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0
                002b  : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0
    MSC (0004): 0004
    LED (0011): 0000  0001  0002  0003  0004
  input props:
    &lt;none&gt;
</pre>

<p>Use the <code>-i</code> option to get more information, including HID mapping
tables and debugging information.</p>

<p>Use the <code>-l</code> option to display textual labels for all event codes.</p>
<pre class="devsite-terminal devsite-click-to-copy">
adb shell su -- getevent -lp /dev/input/event1
</pre>
<p>Example:</p>
<pre>
  name:     "Melfas MMSxxx Touchscreen"
  events:
    ABS (0003): ABS_MT_SLOT           : value 0, min 0, max 9, fuzz 0, flat 0, resolution 0
                ABS_MT_TOUCH_MAJOR    : value 0, min 0, max 30, fuzz 0, flat 0, resolution 0
                ABS_MT_POSITION_X     : value 0, min 0, max 720, fuzz 0, flat 0, resolution 0
                ABS_MT_POSITION_Y     : value 0, min 0, max 1280, fuzz 0, flat 0, resolution 0
                ABS_MT_TRACKING_ID    : value 0, min 0, max 65535, fuzz 0, flat 0, resolution 0
                ABS_MT_PRESSURE       : value 0, min 0, max 255, fuzz 0, flat 0, resolution 0
  input props:
    INPUT_PROP_DIRECT
</code></pre>
<h2 id="showing-live-events">Showing live events</h2>
<p>The following example shows a two-finger multi-touch gesture for a
touchscreen using the Linux multi-touch input protocol "B". The <code>-l</code>
option displays textual labels and the <code>-t</code> option displays
timestamps.</p>

<pre class="devsite-terminal devsite-click-to-copy">
adb shell su -- getevent -lt /dev/input/event1
</pre>

<p>Example:</p>
<pre>
[   78826.389007] EV_ABS       ABS_MT_TRACKING_ID   0000001f
[   78826.389038] EV_ABS       ABS_MT_PRESSURE      000000ab
[   78826.389038] EV_ABS       ABS_MT_POSITION_X    000000ab
[   78826.389068] EV_ABS       ABS_MT_POSITION_Y    0000025b
[   78826.389068] EV_ABS       ABS_MT_SLOT          00000001
[   78826.389068] EV_ABS       ABS_MT_TRACKING_ID   00000020
[   78826.389068] EV_ABS       ABS_MT_PRESSURE      000000b9
[   78826.389099] EV_ABS       ABS_MT_POSITION_X    0000019e
[   78826.389099] EV_ABS       ABS_MT_POSITION_Y    00000361
[   78826.389099] EV_SYN       SYN_REPORT           00000000
[   78826.468688] EV_ABS       ABS_MT_SLOT          00000000
[   78826.468688] EV_ABS       ABS_MT_TRACKING_ID   ffffffff
[   78826.468719] EV_ABS       ABS_MT_SLOT          00000001
[   78826.468719] EV_ABS       ABS_MT_TRACKING_ID   ffffffff
[   78826.468719] EV_SYN       SYN_REPORT           00000000
</pre>
<p class="note"><strong>Note:</strong> <code>getevent</code> timestamps use
the format $SECONDS.$MICROSECONDS in the CLOCK_MONOTONIC timebase. For details,
refer to getevent.c.</p>
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