feat: add udp

udp/udp_client/Cargo.lock

@@ -0,0 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "udp_client"
+version = "0.1.0"

udp/udp_client/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "udp_client"
+version = "0.1.0"
+authors = ["Hatter Jiang <jht5945@gmail.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

udp/udp_client/src/main.rs

@@ -0,0 +1,34 @@
+use std::net::{TcpStream};
+use std::io::{Read, Write};
+use std::str::from_utf8;
+
+fn main() {
+    match TcpStream::connect("localhost:3333") {
+        Ok(mut stream) => {
+            println!("Successfully connected to server in port 3333");
+
+            let msg = b"Hello!";
+            stream.write(msg).unwrap();
+            println!("Sent Hello, awaiting reply...");
+
+            let mut data = [0 as u8; 6]; // using 6 byte buffer
+            match stream.read_exact(&mut data) {
+                Ok(_) => {
+                    if &data == msg {
+                        println!("Reply is ok!");
+                    } else {
+                        let text = from_utf8(&data).unwrap();
+                        println!("Unexpected reply: {}", text);
+                    }
+                },
+                Err(e) => {
+                    println!("Failed to receive data: {}", e);
+                }
+            }
+        },
+        Err(e) => {
+            println!("Failed to connect: {}", e);
+        }
+    }
+    println!("Terminated.");
+}