SHOWKEY(1)                                                    General Commands Manual                                                   SHOWKEY(1)

NAME

       showkey - examine the codes sent by the keyboard

SYNOPSIS

       showkey [-h|--help] [-a|--ascii] [-s|--scancodes] [-k|--keycodes] [-V|--version]

DESCRIPTION

       showkey prints to standard output either the scan codes or the keycode or the `ascii' code of each key pressed.  In the first two modes the
       program runs until 10 seconds have elapsed since the last key press or release event, or until it receives a suitable signal, like SIGTERM,
       from another process.  In `ascii' mode the program terminates when the user types ^D.

       When in scancode dump mode, showkey prints in hexadecimal format each byte received from the keyboard to the standard output. A new line is
       printed when an interval of about 0.1 seconds occurs between the bytes received, or when the internal receive buffer fills up. This can  be
       used  to  determine  roughly,  what byte sequences the keyboard sends at once on a given key press. The scan code dumping mode is primarily
       intended for debugging the keyboard driver or other low level interfaces. As such it shouldn't be of much interest to the regular end-user.
       However,  some  modern  keyboards  have keys or buttons that produce scancodes to which the kernel does not associate a keycode, and, after
       finding out what these are, the user can assign keycodes with setkeycodes(8).

       When in the default keycode dump mode, showkey prints to the standard output the keycode number or each key pressed or released.  The  kind
       of  the  event, press or release, is also reported.  Keycodes are numbers assigned by the kernel to each individual physical key. Every key
       has always only one associated keycode number, whether the keyboard sends single or multiple scan codes when pressing it. Using showkey  in
       this mode, you can find out what numbers to use in your personalized keymap files.

       When in `ascii' dump mode, showkey prints to the standard output the decimal, octal, and hexadecimal value(s) of the key pressed, according
       to he present keymap.

OPTIONS

       -h --help
              showkey prints to the standard error output its version number, a compile option and a short usage message, then exits.

       -s --scancodes
              Starts showkey in scan code dump mode.

       -k --keycodes
              Starts showkey in keycode dump mode. This is the default, when no command line options are present.

       -a --ascii
              Starts showkey in `ascii' dump mode.

       -V --version
              showkey prints version number and exits.

2.6 KERNELS
       In 2.6 kernels key codes lie in the range 1-255, instead of 1-127.  Key codes larger than 127 are returned as three bytes of which the  low
       order 7 bits are: zero, bits 13-7, and bits 6-0 of the key code.  The high order bits are: 0/1 for make/break, 1, 1.

       In  2.6  kernels  raw mode, or scancode mode, is not very raw at all.  Scan codes are first translated to key codes, and when scancodes are
       desired, the key codes are translated back. Various transformations are involved, and there is no guarantee at all that  the  final  result
       corresponds  to what the keyboard hardware did send. So, if you want to know the scan codes sent by various keys it is better to boot a 2.4
       kernel. Since 2.6.9 there also is the boot option atkbd.softraw=0 that tells the 2.6 kernel to return the actual scan codes.

SEE ALSO

       loadkeys(1), dumpkeys(1), keymaps(5), setkeycodes(8)

                                                                    1 Feb 1998                                                          SHOWKEY(1)