how to "hook" a function, in user applications, to a specific interrupt

[stanliao at globalunichip.com]

Dear All,

This problem isn't about busybox but about Linux (or UNIX) applications. I
would like to write a driver for our platform "push-buttons". Then my
uncertainty comes. 1. Is there any standard defined for push-buttons?  2.
If there is no such a standard defined for push-buttons, I might write it
as a character driver. But how to let the application to hook a function
for push-button events? I very appreciate that someone could guide me in
this.

Best Regards,
Stan Liao