Here's an example to get you started. Compile and run with ./progname | tee /dev/tty | aplay

you can also pipe it into other programs like xxd: ./progname | xxd | tee /dev/tty | aplay

#include <stdio.h>

#include <math.h>

int main()

{

  int t;

  for ( t=0; ; t++ ) putchar( t*((t>>7|t>>13)&73&t>>6) );  
}