main.c

#include <stdio.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <string.h>

#define PORT 8080

int main(int argc, char const *argv[])
{

    int server_fd, new_socket; long valread;

    struct sockaddr_in server_addr;
    int addrlen = sizeof(server_addr);

    // minimalist HTTP Header
    char *hello = "HTTP/1.1 200 OK\nContent-Type: text/plain\nContent-Length: 12\n\nHello world!";

    int domain = AF_INET; // IPv4
    int type = SOCK_STREAM; // TCP
    int protocol = 0; // because only one virtual circuit service

    // socket file descriptor
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0)
    {
        perror("In Socket");
        exit(EXIT_FAILURE);
    }


    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY); // long int to network representation
    server_addr.sin_port = htons(PORT); // short int to network representation

    memset(server_addr.sin_zero, '\0', sizeof server_addr.sin_zero);

    if (bind(server_fd, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0)
    {
        perror("In Bind");
        exit(EXIT_FAILURE);
    }

    if (listen(server_fd, 10) < 0) {
        perror("In Listen");
        exit(EXIT_FAILURE);
    }

    while (1)
    {
        printf("\n+++++++ Waiting for new connection ++++++++\n\n");
        if ((new_socket = accept(server_fd, (struct sockaddr *)&server_addr, (socklen_t*)&addrlen)) < 0)
        {
            perror("In Accept");
            exit(EXIT_FAILURE);
        }

        char buffer[30000] = {0};
        valread = read(new_socket, buffer, 30000);
        printf("%s\n",buffer );
        write(new_socket , hello , strlen(hello));
        printf("------------------Hello message sent-------------------\n");
        close(new_socket);
    }

    return 0;
}