chenyuy001/computer-network-2024

README

This README provides information about the simple TCP client (sclient.c) and server (sserver.c) applications. These programs demonstrate basic TCP/IP communication between a client and a server in C language. The client sends a message to the server, and the server responds back after processing the message.

Overview

The Simple TCP Client (sclient.c) reads a message from the standard input (stdin), sends it to a specified server, and then displays the server's response.

The Simple TCP Server (sserver.c) listens for connections on a specified port, reads the message sent by the client, processes it, and sends a response back.

Compilation

Before running the applications, they need to be compiled. You will need a C compiler (e.g., gcc) installed on your system.

To compile the client:

make sclient

To compile the server:

make sserver

To compile or clean all the files:

make all(clean all)

Usage

Server

Run the server by specifying the port number on which it will listen for connections:

./sserver -p [port]

Replace [port] with the actual port number (e.g., 8080).

Client

Run the client by specifying the server IP and port number:

./sclient -p [port] -s [server-ip] < file-to-send.txt

Replace [port] with the server's port number and [server-ip] with the server's IP address.

Features

• Client:
  • Connects to a server specified by IP and port.
  • Sends data read from file to the server.
  • Receives and displays the server's response.
  • Supports both IPv4 and IPv6 connections.
• Server:
  • Listens for connections on a specified port.
  • Accepts connections from clients.
  • Reads and processes received data.
  • Sends a response back to the client.

Limitations

• The client and server are implemented for demonstration purposes and may not cover all edge cases.
• Error handling is basic, primarily for clarity and understanding.

Example Session

1. Start the server:

   ./sserver -p 8080
   

2. In a new terminal, start the client:

   ./sclient -p 8080 -s 127.0.0.1 < file-to-send.txt
   

3. The server receives the message, processes it, and the client displays the response.

Troubleshooting

• Ensure the server is running before starting the client.
• Check if the port number is available and not used by other applications.
• Verify that the server IP address and port number are correct in the client command.