Implementing a Basic Web Server in C

Introduction

A web server is a program that serves web pages to clients (browsers). This guide explores the fundamentals of implementing a simple web server in C and provides sample code to illustrate key concepts and techniques.

Key Web Server Features

A basic web server should include the following features:

• HTTP Protocol Support: Handling incoming HTTP requests and sending responses.
• Static Content Serving: Serving static HTML, CSS, JavaScript, and other files.
• Dynamic Content Generation: Generating dynamic content through server-side scripting.

Sample Code for a Basic Web Server

Let's create a simple C program that serves static HTML content. We'll use socket programming to listen for incoming HTTP requests and respond with a basic HTML page. Here's a basic example:

// Sample web server in C
// (This is a simplified example and not suitable for production use)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
int main() {
    // Server socket setup
    int server_socket = socket(AF_INET, SOCK_STREAM, 0);
    struct sockaddr_in server_address;
    server_address.sin_family = AF_INET;
    server_address.sin_port = htons(80); // HTTP port
    server_address.sin_addr.s_addr = INADDR_ANY;
    // Bind the server socket
    bind(server_socket, (struct sockaddr*)&server_address, sizeof(server_address));
    // Listen for incoming connections
    listen(server_socket, 5);
    printf("Web server is running and listening on port 80...\n");
    while (1) {
// Accept incoming connections
int client_socket = accept(server_socket, NULL, NULL);
// Send an HTTP response
char response[] = "HTTP/1.1 200 OK\r\nContent-Length: 12\r\n\r\nHello, World!";
send(client_socket, response, sizeof(response) - 1, 0);
// Close the client socket
close(client_socket);
    }
    // Close the server socket
    close(server_socket);
    return 0;
}
    

This code represents a basic web server in C that listens on port 80 and responds to incoming HTTP requests with a simple "Hello, World!" message. It's a minimal example, and production web servers are much more complex, supporting multiple file types and dynamic content generation.

Conclusion

Implementing a web server in C involves setting up sockets, handling HTTP requests, and responding with appropriate content. This guide introduced the basics of creating a simple web server and provided sample code for static content serving. To build a production-ready web server, consider using established web server libraries and frameworks.