Socket Server And Client in different languages

[Syed Babu]

Correct me if Im wrong. The socket server and client does not dependent any development languages. Irrespective of the language, they should work fine.

Here is my issue:

My server is being developed using TCL ( Tool Command Language ) and here is the following command to create server:

#Callback function called when the client connected to server
proc ServerOpenCallBack {channel addr port} {
tk_messageBox -message "Client Connected"
}

#Create a socket server
set var [socket -server ServerOpenCallBack 20000]

My Client is developed using C++ and using native OS calls to connect to the socket:


// Socket_Client.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
using namespace std;

#include <Winsock2.h>
#include <Windows.h>


int _tmain(int argc, _TCHAR* argv[])
{
int iResult = -1;
char szPath[128] = "";

WSADATA wsaData;

//Intialize the win socket dll by passing highest version of windows socket specification
WSAStartup(MAKEWORD(2, 2), &wsaData);

//Get the host name
gethostname(szPath, sizeof(szPath));

//Get the host by name and fetch the id address
hostent* pHostEnt = gethostbyname(szPath);
in_addr* pInAddress = (in_addr*)(*pHostEnt->h_addr_list);
char* szIPAddresss = inet_ntoa(*pInAddress);

//Create an unnamed socket for the server
int client_socket_fd = socket(AF_INET,SOCK_STREAM,0 );

//Connect the client to the port
sockaddr_in client_address;
client_address.sin_family = AF_INET;
client_address.sin_addr = *pInAddress;
client_address.sin_port = 20000;
int client_addr_len = sizeof(sockaddr_in);
iResult = connect(client_socket_fd, (struct sockaddr *)&client_address, client_addr_len);

if( iResult != 0 )
{
int iErrCode = WSAGetLastError();
cout<<iErrCode<<endl;
}
char ch = X;
DWORD nbBytesWritten = 0;
int ierr = send( client_socket_fd,&ch,1,0 );


WSACleanup();

return 0;
}


When I ran the above code, the "connect" call fails and returns the error code 10061 ( WSAECONNREFUSED ).

Findings:

• But when I tried to connect the above TCL server with a client written in TCL it connects fine and shows the message box "Client connected". Below is my TCL client code:

set sockVar [socket -async 19.76.34.159 20000]
Where 19.76.34.159 is the IP address of my system.

• Similarly for my C++ client code shown above, if I write server in C++ and it works fine.

Could not find out what is wrong. Your help is appreciated.

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