Linux : How to detect if USB keyboard is plugged and unplugged

Question

Is there any daemon/tool which will trigger some signal/event when usb keyboard is plugged and unplugged from pc ? I need to know in my program when usb keyboard is plugged

Answer 1

udevadm monitor (the udev administration binary) or udev_monitor (in libudev).

Alternately, if you're running in X11 with input hotplugging, you can listen for the XI extension event DevicePresenceNotify.