diff --git a/src/main.rs b/src/main.rs
index e7a11a9..83c2e1d 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,3 +1,54 @@
-fn main() {
-    println!("Hello, world!");
-}
+use std::net::{TcpListener, TcpStream};
+use std::io::{Read, Write};
+use std::env;
+
+enum EnvArg
+    {
+        Client,
+        Server,
+    }
+
+fn take_arg() -> EnvArg
+    {
+        let args:Vec<String> = env::args().collect();
+        match args.len()
+            {
+                1 => println!("Give an argument"),
+                2 => 
+                    {
+                        if args[1] == "c"
+                            {
+                                return EnvArg::Client;
+                            }
+                        else if args[1] == "s"
+                            {
+                                return EnvArg::Server;
+                            }
+                        else 
+                            {
+                                println!("Give valid argument, c or s");
+                            }
+                    },
+                _ => println!("Only one argument is allowed"),
+            }
+        panic!();
+    }
+
+fn client() 
+    {
+        println!("Client");
+    }
+fn server()
+    {
+        println!("Server");
+    }
+
+fn main() 
+    {
+        println!("Hello, world!");
+        match take_arg() 
+            {
+                EnvArg::Client => client(),
+                EnvArg::Server => server()
+            }
+    }