C Sokcet HELP :P

First i want to say hi all of toy i am new here my name is shellc0de as you see now i have one problem I make simple socket(server) in C tat when he accept connection send string to client.But when i compile & run and connect with telnet i get blank outpu,but thats not a point i solve that.This process is finished very fast that is problem whyi didn't get output now i put Sleep(1); and programs runs perefct but i need help to done this without Sleep() function. Thanks
Here is code:

Code:

#include <stdio.h>
#include <windows.h>


int main(void)
{
    WSADATA wsaData;
    if(WSAStartup(MAKEWORD(2,0),&wsaData)!=0)
    {
        printf("WSAStartup failed!");
    }
    // Some variables
    int old_socket,new_socket,addrlen;
    addrlen=sizeof(struct sockaddr_in);
    char *message="This is a message to send!\r\n\r\n";
    struct sockaddr_in addr;


    // Creating a socket
    old_socket=socket(AF_INET,SOCK_STREAM,0);
    if(!old_socket){
        printf("Can't create socket!\n");
    }
    printf("Socket is created.\n");


    // Binding a socket to a port
    addr.sin_family=AF_INET;
    addr.sin_addr.s_addr=INADDR_ANY;
    addr.sin_port=htons(7000);
    bind(old_socket,(struct sockaddr *)&addr,sizeof(addr));
    printf("Socket is binded on port %d\n",htons(addr.sin_port));


    // Listening for connection
    listen(old_socket,3);
    printf("Listening...\n");


    // Accepting a connection
    new_socket=accept(old_socket,(struct sockaddr *)&addr,&addrlen);
    if(!new_socket){
        printf("Can't accept connection!\n");
    }
    printf("Connection accepted.\n");


    // Sendig data to a connection
    send(new_socket,message,strlen(message),0);
    printf("Data has been send.\n");
    Sleep(1);


    // Closing connection
    close(new_socket);
    printf("Socket is closed.\n");


}

Are you sure you don't get compiler errors or warnings?

You initialise addrlen to the sizeof a struct you have not yet declared.

It's also normal to initialise the struct before using it using memset or

Code:

 struct  sockaddr_in addr = {0};

Well I just added this code before the bind()

Code:

    int yes = 1;
    if (setsockopt(old_socket, SOL_SOCKET, SO_REUSEADDR, &yes,
        sizeof(int)) == -1) {
      perror("setsockopt");
      exit(1);
    }

and it all seems fine.

Code:

// server
$ ./a.out 
Socket is created.
Socket is binded on port 7000
Listening...
Connection accepted.
Data has been send.
Socket is closed.

// client
$ telnet localhost 7000
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
This is a message to send!

Connection closed by foreign host.

Without the SO_REUSEADDR, I just get
$ telnet localhost 7000
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused
until the socket has timed out.

Adding
close(old_socket);
is probably a good idea as well.

Originally Posted by gemera

You initialise addrlen to the sizeof a struct you have not yet declared.


[/code]

Sorry,ignore that.

There's some Linux/Windows bleed going on here methinks!

You used close() which is the way to close sockets in Linux.

So this should have given you a compiler warning.

In Windows the function is closesocket().

Which means you need to use the Windows version of Salem's setsockopt() code or

Code:

const char *yes = "TRUE";

if (setsockopt(old_socket, SOL_SOCKET, SO_REUSEADDR, yes,sizeof(yes)))
{
     perror("setsockopt");
     exit(1);
}

Nothing :P again same problem :3 Salem-i am on win platform i use codeblocks with mingw,maybe that code works fine under linux.

Code:

intyes = 1;if (setsockopt(old_socket, SOL_SOCKET, SO_REUSEADDR, &yes,
    sizeof(int)) == -1) {
  perror("setsockopt");
  exit(1);
}

This code works thanks,i just needed to put that and to use closesocket() Thanks.