TCP echo server doesn't accept client - c

Question

I'm trying to make an echo client server in C. The problem is, when I start the server and run the client code, in client shell it says "Connected" but in server shell it still says "Waiting for connection". (Server doesn't say "accept failed". It says "Waiting for connection" forever). I think server is not accepting client and therefore if I write anything from client shell it doesn't come back.
I would appreciate if I can get any help.
Here is server code:
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
int socket_desc, client_sock, c, read_size;
struct sockaddr_in server, client;
char client_message[2000];
//create socket
socket_desc = socket(AF_INET, SOCK_STREAM, 0);
if(socket_desc == -1)
{
printf("Socket couldn't created\n");
}
puts("Socket created");
//prepare the sockaddr_in structure
server.sin_family = AF_INET;
server.sin_addr.s_addr = INADDR_ANY;
server.sin_port = htons( 8888 );
//bind
if( bind(socket_desc,(struct sockaddr *)&server, sizeof(server)) < 0)
{
//print the error message
perror("bind failed");
return 1;
}
puts("bind done");
//Listen
listen(socket_desc , 3)
//Accept and incoming connection
puts("Waiting for incoming connections...");
c = sizeof(struct sockaddr_in);
while(1)
{
//accept connection from an incoming client
client_sock = accept(socket_desc, (struct sockaddr *)&client, (socklen_t *)&c);
if(client_sock < 0)
{
perror("accept failed");
return 1;
}
}
puts("Connection accepted");
//Recieve message from client
while( (read_size = recv(client_sock , client_message , 2000 , 0))>0)
{
//Send the message back to client
write(client_sock , client_message , strlen(client_message));
}
if(read_size == 0)
{
puts("Client disconnected");
}
else if(read_size == -1)
{
perror("recv failed");
}
return 0;
}
Here is the client code:
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
int main(int argc , char *argv[])
{
int sock;
struct sockaddr_in server;
char message[1000] , server_reply[1000];
//Create socket
sock = socket(AF_INET , SOCK_STREAM , 0);
if(sock == -1)
{
printf("Could not create socket");
}
puts("Socket created");
server.sin_addr.s_addr = inet_addr("127.0.0.1");
server.sin_family = AF_INET;
server.sin_port = htons( 8888 );
//Connect to remote server
if(connect(sock, (struct sockaddr *)&server, sizeof(server))<0)
{
perror("connect failed");
return 1;
}
puts("Connected\n");
//Keep communicating with server
while(1)
{
printf("Enter message: ");
scanf("%s", message);
//Send some data
if(send(sock, message, strlen(message), 0)<0)
{
puts("Send failed");
return 1;
}
//Recieve a reply from server
if( recv(sock, server_reply, 1000, 0)<0)
{
puts("recv failed");
}
puts("Server reply: ");
puts(server_reply);
bzero(message, 1000);
bzero(server_reply, 1000);
}
close(sock);
return 0;
}

Answer 1

You accept new clients in a infinite loop. So even if a client is detected the code will wait for an other client to connect.
If you want to make a single client server you can just remove the loop around the accept(). Example here
If you want to make a multiple client server you can thread your accept and store all your opened file descriptor. Example here

Answer 2

In your server code you never leave this infinite loop:
while(1)
{
//accept connection from an incoming client
client_sock = accept(socket_desc, (struct sockaddr *)&client, (socklen_t *)&c);
if(client_sock < 0)
{
perror("accept failed");
return 1;
}
}
You should either fork/thread or use the select function.