client server communication

I executed the simple client server application, which is inside the l4 pkg directory of l4re. But, in that application, input is given inside the program itself. I want to take the input from user and send it to server through IPC GATE and the server has to respond to client (which will again be given by user). I tried using scanf, cin, sscanf, io.read...but the program takes only the garbage values. I am unable to give input in qemu... It would be helpful if some sample code is given for such kind of applications wherein the user inputs at run time... Gayathri