UNIX for Advanced & Expert Users

I want write a program where I call the pause() function to wait for any signal. Now I have registered the SIGIO signal with the following lines of code:

const int on = 1;

fcntl(STDIN_FILENO,F_SETOWN,getpid());

ioctl(STDIN_FILENO, FIOASYNC, &on);
ioctl(STDIN_FILENO, FIONBIO, &on);

signal(SIGIO,catchSIGIO);

then I called the pause() function. The body of the catchSIGIO() is given below:

void catchSIGIO(int num){
printf("INSIDE SIGIO\n");
}

The program compiles alright. When I run the program, it halts/pauses at the pause() function call. Then when I type something in the keyboard, the SIGIO signal is NOT generated (I guess) because nothing happens. The program remains stuck at the pause() function. I can ONLY get out by pressing ctrl+C.

But I want to detect ANY KEY PRESS by SIGIO signal or any other signal (if there is any).

Can anyone help me on this issue? Thanks in advance.