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I'm fairly new to ubuntu and I've started to search around everywhere and check everything! Recently I saw these files at /dev/input/eventX, js0, mice, mouseX. By printing the output using "cat" I realized they are somehow responsible for mouse and keyboard input but the output had an strange character encoding (even for the keyboard).

My questions are,

  1. what are these files and how can I interpret the data of these files?
  2. Are there any other places that I can access the input/output of my Ubuntu machine?
  3. And are there any ebooks, manual or something similar that I can check the duty and structure of ubuntu system files? (i.e. to find the answer of such question)


To make the data of the file more readable, I used hexdump:

sudo cat /dev/input/by-id/<nameofthemouse> | hexdump -C


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For more information on the filesystem layout, see and for documentation on the filesystem see – user76204 Nov 2 '12 at 15:59

This is the location where device files for your input devices are located.

Device Files: (taken from Wikipedia)

In Unix-like operating systems, a device file or special file is an interface for a device driver that appears in a file system as if it were an ordinary file...They allow software to interact with a device driver using standard input/output system calls, which simplifies many tasks and unifies user-space I/O mechanisms.

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/dev is system directory that contains all Hardware device related files. Check out this manual for Ubuntu Filesystem Tree Overview and this also.

enter image description here

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Thanks. But how can I interpret this data? To me they look like of bunch of strange characters. Please kindly refer to my questions again. Let's say, how can I read (if possible) the cursor location from this file? – Pouya Nov 2 '12 at 11:00
I have indicated that they are system files necessary for devices. You search System Moniter tool in dash for input output network stataic – K.K Patel Nov 2 '12 at 11:17

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