supercocoa · December 14, 2021 07:34 · Aug 29, 2019 · Jun 17, 2013
diff --git a/client.go b/client.go
@@ -1,7 +1,8 @@
 package main
 
 import (
-    "log"
+	"os"
+    	"log"
 	"net"
 	"strconv"
 	"strings"
@@ -16,11 +17,12 @@ func SocketClient(ip string, port int) {
 	addr := strings.Join([]string{ip, strconv.Itoa(port)}, ":")
 	conn, err := net.Dial("tcp", addr)
 
-	defer conn.Close()
-
 	if err != nil {
 		log.Fatalln(err)
+		os.Exit(1)
 	}
+
+	defer conn.Close()
 
 	conn.Write([]byte(message))
 	conn.Write([]byte(StopCharacter))

diff --git a/server.go b/server.go
@@ -18,11 +18,14 @@ const (
 func SocketServer(port int) {
 
 	listen, err := net.Listen("tcp4", ":"+strconv.Itoa(port))
-	defer listen.Close()
+
 	if err != nil {
 		log.Fatalf("Socket listen port %d failed,%s", port, err)
 		os.Exit(1)
 	}
+
+	defer listen.Close()
+
 	log.Printf("Begin listen port: %d", port)
 
 	for {

diff --git a/client.go b/client.go
@@ -0,0 +1,44 @@
+package main
+
+import (
+    "log"
+	"net"
+	"strconv"
+	"strings"
+)
+
+const (
+	message       = "Ping"
+	StopCharacter = "\r\n\r\n"
+)
+
+func SocketClient(ip string, port int) {
+	addr := strings.Join([]string{ip, strconv.Itoa(port)}, ":")
+	conn, err := net.Dial("tcp", addr)
+
+	defer conn.Close()
+
+	if err != nil {
+		log.Fatalln(err)
+	}
+
+	conn.Write([]byte(message))
+	conn.Write([]byte(StopCharacter))
+	log.Printf("Send: %s", message)
+
+	buff := make([]byte, 1024)
+	n, _ := conn.Read(buff)
+	log.Printf("Receive: %s", buff[:n])
+
+}
+
+func main() {
+
+	var (
+		ip   = "127.0.0.1"
+		port = 3333
+	)
+
+	SocketClient(ip, port)
+
+}
diff --git a/server.go b/server.go
@@ -0,0 +1,86 @@
+package main
+
+import (
+    "bufio"
+	"io"
+	"log"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+)
+
+const (
+	Message       = "Pong"
+	StopCharacter = "\r\n\r\n"
+)
+
+func SocketServer(port int) {
+
+	listen, err := net.Listen("tcp4", ":"+strconv.Itoa(port))
+	defer listen.Close()
+	if err != nil {
+		log.Fatalf("Socket listen port %d failed,%s", port, err)
+		os.Exit(1)
+	}
+	log.Printf("Begin listen port: %d", port)
+
+	for {
+		conn, err := listen.Accept()
+		if err != nil {
+			log.Fatalln(err)
+			continue
+		}
+		go handler(conn)
+	}
+
+}
+
+func handler(conn net.Conn) {
+
+	defer conn.Close()
+
+	var (
+		buf = make([]byte, 1024)
+		r   = bufio.NewReader(conn)
+		w   = bufio.NewWriter(conn)
+	)
+
+ILOOP:
+	for {
+		n, err := r.Read(buf)
+		data := string(buf[:n])
+
+		switch err {
+		case io.EOF:
+			break ILOOP
+		case nil:
+			log.Println("Receive:", data)
+			if isTransportOver(data) {
+				break ILOOP
+			}
+
+		default:
+			log.Fatalf("Receive data failed:%s", err)
+			return
+		}
+
+	}
+	w.Write([]byte(Message))
+	w.Flush()
+	log.Printf("Send: %s", Message)
+
+}
+
+func isTransportOver(data string) (over bool) {
+	over = strings.HasSuffix(data, "\r\n\r\n")
+	return
+}
+
+func main() {
+
+	port := 3333
+
+	SocketServer(port)
+
+}