tcpecho.c

/************
 tcp_server.c
************/
#include<stdio.h>
#include<stdlib.h>

#include<sys/types.h>
#include<sys/socket.h>

#include<netinet/in.h>

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

        //Create server messages
        char server_messages[256];

        //Create server socket
        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(3400);
        server_address.sin_addr.s_addr = INADDR_ANY;

        //Bind socket to specified IP and PORT
        bind(server_socket, (struct sockaddr*) &server_address, sizeof(server_address));

        listen(server_socket, 5);
        int client_socket;
        client_socket = accept(server_socket, NULL, NULL);
        while(1){
                //Send messages
                recv(client_socket, &server_messages, sizeof(server_messages), 0);
                printf("Message from client: %s",server_messages);
                send(client_socket, server_messages, sizeof(server_messages), 0);
        }
        close(server_socket);
        return 0;
}

/************
 tcp_client.c
************/
#include<stdio.h>
#include<stdlib.h>

#include<sys/types.h>
#include<sys/socket.h>

//Struct for handling internet addresses
#include<netinet/in.h>

int main(int argc, char* argv[]) {
        //Create a socket
        int network_socket = socket(AF_INET, SOCK_STREAM, 0);

        struct sockaddr_in server_address;
        server_address.sin_family = AF_INET;
        server_address.sin_port = htons(atoi(argv[1]));
        //server_address.sin_addr.s_addr = INADDR_ANY;
        server_address.sin_addr.s_addr = inet_addr(argv[2]); //set server's address in the second parameter

        //Check connection status
        int connect_status = connect(network_socket, (struct sockaddr *) &server_address, sizeof(server_address));
        if(connect_status == -1) {
                printf("error");
        }

        while(1) {
                //Send messages to server
                char messages[256];
                fgets(messages, 256, stdin);
                send(network_socket, messages, sizeof(messages),0);

                //Receive data from server
                char server_response[256];
                recv(network_socket, &server_response, sizeof(server_response), 0);

                //Print out the result returned from server
                printf("Message from server: %s", server_response);
        }

        //Close socket
        close(network_socket);

        return 0;
}