Linux keyboard event capturing /dev/inputX

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I was trying to capture keyboard events. e.g. I want to drill down a keylogger from the scratch. After 2 hours of fighting I found the following

neel@pc1$ ls -l /dev/input/by-id
lrwxrwxrwx 1 root root 9 2010-05-05 21:33 usb-Plus_More_Enterprise_LTD._USB-compliant_keyboard-event-kbd -> ../event1
lrwxrwxrwx 1 root root 9 2010-05-05 21:33 usb-Plus_More_Enterprise_LTD._USB-compliant_keyboard-event-mouse -> ../event2
lrwxrwxrwx 1 root root 9 2010-05-05 21:33 usb-Plus_More_Enterprise_LTD._USB-compliant_keyboard-mouse -> ../mouse1

But when I tried to

neel@pc1$ sudo cat /dev/input/usb-Plus_More_Enterprise_LTD._USB-compliant_keyboard-event-kbd

It yields nothing THERE WAS NO OUTPUT

after a bit more searching Now I am thinking probabbly something in Xorg blocks it.

So Any more Information ?? and atthe end of the say how can I read the input from that file ?? or is there any other way of capturing keyboard events ??


Thank you for the clue about ls -l /dev/input/by-id it helped me a lot !.

defenderdz@defenderdz-pc:~$ ls -l /dev/input/by-id | grep kbd
lrwxrwxrwx 1 root root  9 nov.  28 14:04 usb-Logitech_USB_Receiver-event-kbd -> ../event7
lrwxrwxrwx 1 root root 10 nov.  29 00:33 usb-NOVATEK_USB_Keyboard-event-kbd -> ../event26
lrwxrwxrwx 1 root root  9 nov.  28 14:04 usb-SONiX_USB_DEVICE-event-kbd -> ../event3
defenderdz@defenderdz-pc:~$ 

'kbd' is the suffix used for keyboard devices (I have 3 keyboards connected).

Your error is that you're accessing the wrong folder :

/dev/input/ instead of /dev/input/by-id

In my example the correct path is :

defenderdz@defenderdz-pc:~$ sudo cat /dev/input/by-id/usb-NOVATEK_USB_Keyboard-event-kbd
���]�I���]�I���]�Ia���]�b���]�b���]�b���]�����]�����]��s���]����]����]����]�>
���]�>
 ���]�>
d���]�8
       ���]�8
              ���]�8
                    ���]�����]�����]��s���]H|���]H|���]H|���]�����]�� ���]��d���]Ǵ���]Ǵ ���]Ǵ

In your case

neel@pc1$ sudo cat /dev/input/by-id/usb-Plus_More_Enterprise_LTD._USB-compliant_keyboard-event-kbd

I'm not saying that it's the best solution but it works fine for me. You can even create an automatic detection of the keyboard by parsing the ls result ...

Linux keyboard events capture / dev / inputX, You are reading the wrong device. Or try all / dev / input / event * or look in /var/ log/Xorg.0.log, for which the device is used for your keyboard. If you download the source code, and have a look at the logkeys.cc file, you will find one method how to auto-detect which /dev/input/event is used by your keyboard. This will let you read raw scan codes from the keyboard, regardless of which program currently has focus.


Hello,

I was recently trying to accomplish something similar.

Have a look at the logkeys project:

http://code.google.com/p/logkeys/

If you download the source code, and have a look at the logkeys.cc file, you will find one method how to auto-detect which /dev/input/event is used by your keyboard. This will let you read raw scan codes from the keyboard, regardless of which program currently has focus. The logkeys program also shows how to translate the scan codes into characters, and other useful tricks.

Hope this helps,

Markus.

monitoring events (keyboard, mouse) in X, Note, if you do this, you'll make it pretty difficult to actually interact with any program since xev will be capturing all input. xev -root comes with an implied " YMMV". Hi, Is there any way to capture/record the input events from keyboard, as well as from mouse using C. Thanks in advance | The UNIX and Linux Forums


A simple grep operation on the /proc/bus/input/devices file will yield all the keyboards plugged into the machine:

 grep -E  'Handlers|EV=' /proc/bus/input/devices | \
 grep -B1 'EV=120013' | \
 grep -Eo 'event[0-9]+'

Where EV=120013 is the bitmask for events supported by the device. As explained here.

This is the way it is implemented in logkeys

Reading Raw Keyboard Input – Raspberry Pi Projects, Functions like getchar() let you capture keyboard input, but in limited ways in the /dev/input/ directory, but if you have other inputs or on other Linux systems� To clarify, linux is NOT seeing the pedal presses as input. It does recognize the USB device, but xev gives no output for pedal presses. I have seen reports of people succesefully using the pedal under WINE for transcription software, but that must work in a Windows way and does not give what I want (which is making the pedal look like a keyboard to all native linux apps).


You are reading the wrong device. Either try all /dev/input/event* or look in /var/log/Xorg.0.log for which device is used for your keyboard.

Show keys pressed in Linux, Wireless PID:1028 id=9 [slave pointer (2)] ⎣ Virtual core keyboard id=3 In some situations, it is better than xev as it shows keys even when a key is already captured. /dev/input/event13: ELAN Touchscreen Select the device event number� A special event type, EV_SYN, is used to separate input events into packets of input data changes occurring at the same moment in time. In the following, the term “event” refers to a single input event encompassing a type, code, and value. The input protocol is a stateful protocol.


I'd recommend using the evtest application, it lists all your input devices and allows you monitor their events.

Linux keyboard event capturing /dev/inputX, I was trying to capture keyboard events. e.g. I want to drill down a keylogger from the scratch. After 2 hours of fighting I found the following. $ sudo cat /dev/input/by-path/platform-i8042-serio-0-event-kbd Garbage ASCII was sent to my terminal on key press and release events starting with the return (enter) key when I began the output using cat.


3. Remote controller tables — The Linux Kernel documentation, The modules register the remote as keyboard within the linux input layer. it is possible for applications to access the remote via /dev/input/event devices. KEY_CAMERA, Take a picture of the image, CAMERA ICON / CAPTURE / SNAPSHOT input modes, SOURCE / SELECT / DISPLAY / SWITCH INPUTS / VIDEO. The first argument to the ioctl function is an open file descriptor for the event device node (for example, /dev/input/event0). Notice that you have to pass a pointer to the integer variable, not the variable itself, as the third argument to the ioctl call. Listing 1.


Linux simulate keyboard input, It can be programmed with the same developer environment as an Arduino board . for linux that captures the Screen of an Android phone and forwards inputs from the It captures all keys, even onscreen keyboard events are also captured. Linux keyboard event capturing /dev/inputX. The TTY demystified. Real teletypes in the 1940s. The TTY subsystem is central to the design of Linux, and UNIX in general. Unfortunately, its importance is often overlooked, and it is difficult to find good introductory articles about it.


Linux keyboard event capturing /dev/inputX, I was trying to capture keyboard events. e.g. I want to drill down a keylogger from the scratch. After 2 hours of fighting I found the following. When a keyboard event occurs, the Linux kernel communicates it through these event files using a format that is described in Linux Kernel Input. Each read event will return a 'struct input_event' which is described at the link just mentioned. Note that the above example only gives you 'keycodes' (not ASCII) so you have to decode these to actual 'keys' (explained in a later section). The fact that this example sources the events from /dev/input/event* shows that this application is collecting