Detecting keyboard state from shell
Posted: Tue 14 May 2013, 11:58
Barry discussed the needs here (second comment): http://bkhome.org/blog2/?viewDetailed=00238. So I went googling for a while, found the answer here: http://stackoverflow.com/questions/3649 ... e-in-linux and tidy it up a little bit, as attached.
Usage: kbstate key [devpath]
Returns: 0 if key is pressed, 1 otherwise, 255 for errors.
"key" is either lshift, rshift, lalt, ralt, lctrl, or rctrl (that's left/right shifts, left/right alts, left/right controls) in English keyboard, not sure the equivalents in others. If you hack the source you can easily check for other keys too.
"devpath" is the path to the Linux's keyboard event device. The default value is "/dev/input/by-path/platform-i8042-serio-0-event-kbd" (that is, the built-in PS/2 keyboard) but most of the time you would specify /dev/input/event5 or something. Scan /proc/bus/input/devices, find a device whose handlers is "kbd", and you know which /dev/input/eventXXX you need to specify.
If you need to test multiple keyboards (PS/2, USB, etc) you will need to call kbstate multiple times, one for each devpath.
To compile, just use your favorite compiler like this: "gcc -o kbstate kbstate.c". I've got it compiled statically under 64-bit musl, 32-bit and 64-bit aboriginal cross compiler.
Enjoy.
cheers!
EDIT: add 32-bit and 64-bit static binaries for convenience. Should work in all puppies, 32 and 64-bit.
Usage: kbstate key [devpath]
Returns: 0 if key is pressed, 1 otherwise, 255 for errors.
"key" is either lshift, rshift, lalt, ralt, lctrl, or rctrl (that's left/right shifts, left/right alts, left/right controls) in English keyboard, not sure the equivalents in others. If you hack the source you can easily check for other keys too.
"devpath" is the path to the Linux's keyboard event device. The default value is "/dev/input/by-path/platform-i8042-serio-0-event-kbd" (that is, the built-in PS/2 keyboard) but most of the time you would specify /dev/input/event5 or something. Scan /proc/bus/input/devices, find a device whose handlers is "kbd", and you know which /dev/input/eventXXX you need to specify.
If you need to test multiple keyboards (PS/2, USB, etc) you will need to call kbstate multiple times, one for each devpath.
To compile, just use your favorite compiler like this: "gcc -o kbstate kbstate.c". I've got it compiled statically under 64-bit musl, 32-bit and 64-bit aboriginal cross compiler.
Enjoy.
cheers!
EDIT: add 32-bit and 64-bit static binaries for convenience. Should work in all puppies, 32 and 64-bit.
