Question

Implement the following socket programming in C (b) Chat Application using TCP

Answer 1

TCP CLIENT

#include<sys/socket.h>
#include<stdio.h>
#include<string.h>
#include<netdb.h>
#include<stdlib.h>

int main()
{
    char buf[100];
    int k;
    int sock_des;
    struct sockadder_in client;
    memset(&client,0,sizeof(client));
    sock_des=socket(AF_INET,SOCK_STREAM,0);

    if(sock_des==-1)
    {
        printf("Error in socket creation");
        exit(1);
    }

    client.sin_family=AF_INET;
    client.sin_adder.s_adder=INADDR_ANY;
    client.sin_port=3002;

    k=connect(sock_des,(struct sockadder*)&client,sizeof(client));
    if(k==-1)
    {
        printf("Error in connecting to server");
        exit(1);
    }

    while(1)
    {
        printf("\nEnter data to be send to server: ");
        fgets(buf,100,stdin);
        if(strncmp(buf,"end",3)==0)
            break;

        k=send(sock_des,buf,100,0);
        if(k==-1)
        {
            printf("Error in sending");
            exit(1);
        }

        k=recv(sock_des,buf,100,0);
        if(k==-1)
        {
            printf("Error in receiving");
            exit(1);
        }

        printf("Message got from server is : %s",buf);
    }
    close(sock_des);
   

TCP SERVER

#include<sys/socket.h>
#include<stdio.h>
#include<string.h>
#include<netdb.h>
#include<stdlib.h>
int main()
{
    char buf[100];
    int k;
    socklen_t len;
    int sock_desc,temp_sock_desc;
    struct sockaddr_in server,client;

    memset(&server,0,sizeof(server));
    memset(&client,0,sizeof(client));

    sock_desc=socket(AF_INET,SOCK_STREAM,0);
    if(sock_desc==-1)
    {
        printf("Error in socket creation");
        exit(1);
    }

    server.sin_family=AF_INET;
    server.sin_addr.s_addr=inet_addr("127.0.0.1");
    server.sin_port=3002;

    k=bind(sock_desc,(struct sockaddr*)&server,sizeof(server));
    if(k==-1)
    {
        printf("Error in binding");
        exit(1);
    }

    k=listen(sock_desc,20);
    if(k==-1)
    {
        printf("Error in listening");
        exit(1);
    }

    len=sizeof(client);//VERY IMPORTANT
    temp_sock_desc=accept(sock_desc,(struct sockaddr*)&client,&len);
    if(temp_sock_desc==-1)
    {
        printf("Error in temporary socket creation");
        exit(1);
    }

    while(1)
    {
        k=recv(temp_sock_desc,buf,100,0);
        if(k==-1)
        {
            printf("Error in receiving");
            exit(1);
        }

        printf("Message got from client is : %s",buf);
        printf("\nEnter data to be send to client: ");

        fgets(buf,100,stdin);
        if(strncmp(buf,"end",3)==0)
            break;

        k=send(temp_sock_desc,buf,100,0);
        if(k==-1)
        {
            printf("Error in sending");
            exit(1);
        }
    }
    close(temp_sock_desc);

    exit(0);
    return 0;
}