How to use listener.d example?

[Marcin]

https://github.com/dlang/dmd/blob/master/samples/listener.d

Can some one add more comment to that example?

I need to make code that connects to local application, very 
similar to this.

Assumptions:
1. Create an application that listens to arguments.
2. Create an application that will send arguments to the 
application mentioned above.
3. The application will return the sine (argument) to the client.
4. All communication must be realized via console.

input:
1

1,2,3

4 5

44

Output:
"a =" 1 "sin (a) =" 0.84147

"a =" 1 "sin (a) =" 0.84147
"a =" 2 "sin (a) =" 0.9092
"a =" 3 "sin (a) =" 0.14112

"a =" 4 "sin (a) =" -0.756
"a =" 5 "sin (a) =" 0.9589

"a =" 44 "sin (a) =" 0.0177

Can some one help me write a server and client app?
I will use it to create more complicated application.