...keysniffer was initially written with the US keyboard (and conforming laptops) in mind. By default it shows human-readable strings for the keys pressed. However, as keyboards evolved, more keys got added. So the module now supports a module parameter codes which shows the keycode shift_mask pair in hex (codes=1) or decimal (codes=2). You can lookup the keycodes in /usr/include/linux/input-event-codes.h.
The keypress logs are recorded in debugfs as long as the module is loaded. Only root or sudoers can read the log. The module name has been camouflaged to blend-in with other kernel modules.
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