my need or requirement may sound funny, also there will be a question, why a driver program to do this? but the answer is simple, we need a driver program

Let me just explain what i am looking for is,
A simple linux keboard driver program which should detect a key combination [preferrably, ctrl + k], up on pressing this combination, driver should generate a SIGUSR1 signal and it should send this signal to another program.
I have written [not my own, through google and other resources] the driver program to detect ctrl + k and a small application program to act on the signal. Now I am facing a problem in sending the signal from driver program to application program

If i directly use application program's pid in my keyboard driver program, this can be achieved. But I need a more generic approach, because each time executing the application program and geting the pid will be tough.
I tried what ever i could do, i did lot of googling too, but couldnt get any good solution anywhere;(.
I would be greatful if i get any help or suggestions in this regard.