I opened the two on a computer interface, a as a server, one for the client, don't know the login that way right, list of users show no

The code is as follows:

 the UpdateData (); 
If (LocaIP IsBlank ()) 
{
AfxMessageBox (" set up the machine IP address, please!" ); 
return; 
} 
If (locaPort. IsEmpty ()) 
{
AfxMessageBox (please specify the communication port number! "" ); 
return; 
} 

//initialize the socket and binding 
WSADATA WSADATA; 
Int iErrorCode; 
If (WSAStartup (MAKEWORD (2, 1), & amp; WsaData))//calls the Windows Sockets DLL 
{
M_MessageList. ReplaceSel (" Winsock unable to initialize! \r\n"); 
WSACleanup (); 
return; 
} 
M_MessageList. ReplaceSel (" began to create a Socket... \r\n"); 
SelfRcvSocket=socket (PF_INET, SOCK_DGRAM, 0);//create the native process of Socket, type SOCK_DGRAM, connectionless communication 
If (SelfRcvSocket==INVALID_SOCKET) 
{
M_MessageList. ReplaceSel (" failed to create a socket! \r\n"); 
return; 
} 

//get the native process of IP and port 
BYTE nFild [4]. 
Cstrings sIP; 
NFild LocaIP. GetAddress (nFild [0], [1], nFild [2], nFild [3]). 
SIP. The Format (" % d % d, % d, % d ", nFild [0], nFild [1], nFild [2], nFild [3]). 
M_sockSelfRcvAddr. Sin_family=AF_INET; 
M_sockSelfRcvAddr. Sin_addr. S_un. S_addr=inet_addr (sIP); 
M_sockSelfRcvAddr. Sin_port=htons (atoi (locaPort)); 

//to bind the socket and the native process 
If (bind (SelfRcvSocket, (LPSOCKADDR) & amp; M_sockSelfRcvAddr, sizeof (m_sockSelfRcvAddr))==SOCKET_ERROR) 
{
M_MessageList. ReplaceSel (" binding failed! \r\n"); 
return; 
} 
IErrorCode=WSAAsyncSelect (SelfRcvSocket m_hWnd, WM_CLIENT_READCLOSE, FD_READ); 
If (iErrorCode==SOCKET_ERROR) 
{
M_MessageList. ReplaceSel (" WSAAsyncSelect set failed! - used to connect the request message \ r \ n "); 
return; 
} 
M_MessageList. ReplaceSel (" the native process start-up success! \r\n"); 
M_MessageList. ReplaceSel (" address "+ sIP + + locaPort" port "); 
This - & gt; SetWindowTextA (" the native process (" + sIP + ":" + locaPort + ") is running... - ptopTalker "); 

//interface 
M_Start. EnableWindow (false); 
M_Stop. EnableWindow (true); 
LocaIP. EnableWindow (false); 
M_LcaPrt. EnableWindow (false); 
M_Login. EnableWindow (true); 
SevrIP. EnableWindow (true); 
M_SvrPrt. EnableWindow (true); 
M_nicnam. EnableWindow (true); 
M_MessageList. EnableWindow (true); 
M_exit. EnableWindow (false); 
M_nicnam. SetFocus (); 
//
return; 
//ADD 

CDialog: : OnOK (); 
} 

Void CP2PTalkerDlg: : OnStop () 
{
//TODO: add the control notification handler code 
//ADD 
//when the program stops running, to empty SOCKET 
M_MessageList. ReplaceSel (" \ r \ n are closing the Socket... \r\n"); 
Closesocket (SelfRcvSocket); 
WSACleanup (); 
Stop running m_MessageList. ReplaceSel (" the native process. \r\n"); 
This - & gt; PtopTalker SetWindowTextA (" "); 

//interface 
M_Start. EnableWindow (true); 
M_Stop. EnableWindow (false); 
LocaIP. EnableWindow (true); 
M_LcaPrt. EnableWindow (true); 
M_exit. EnableWindow (true); 
M_Login. EnableWindow (false); 
M_nicnam. EnableWindow (false); 
SevrIP. EnableWindow (false); 
M_SvrPrt. EnableWindow (false); 
LocaIP. SetFocus (); 
//
//ADD 
} 

Void CP2PTalkerDlg: : OnLogin () 
{
//TODO: add the control notification handler code 
//ADD 
//input validation 
The UpdateData (); 
If (nickname. IsEmpty ()) 
{
AfxMessageBox (" give themselves a nickname!" ); 
return; 
} 
If (SevrIP IsBlank ()) 
{
AfxMessageBox (" please fill out the chosen for P2P server host IP address!" ); 
return; 
} 
If (sevrPort. IsEmpty ()) 
{
AfxMessageBox (" please specify port of P2P service process!" ); 
return; 
} 

BYTE nFild [4]. 
Cstrings sIP; 
//generated login registration message 
NFild LocaIP. GetAddress (nFild [0], [1], nFild [2], nFild [3]). 
SIP. The Format (" % d % d, % d, % d ", nFild [0], nFild [1], nFild [2], nFild [3]). 
RegisterAddr="RGST_ADDR;"; 
RegisterAddr +=nickname + ", "+ sIP; 
RegisterAddr +=":" + locaPort; 

//get the P2P service process IP and port 
NFild SevrIP. GetAddress (nFild [0], [1], nFild [2], nFild [3]). 
SIP. The Format (" % d % d, % d, % d ", nFild [0], nFild [1], nFild [2], nFild [3]). 

//send a message 
This - & gt; StartSndSocket (RegisterAddr, sIP, sevrPort); 
This - & gt; SetWindowTextA (" logged-in P2P server (" + sIP + ":" + sevrPort + ") - ptopTalker "); 

//interface 
M_Stop. EnableWindow (false); 
M_Login. EnableWindow (false); 
M_Logout. EnableWindow (true); 
SevrIP. EnableWindow (false); 
M_SvrPrt. EnableWindow (false); 
M_nicnam. EnableWindow (false); 
M_UserList. EnableWindow (true); 
M_EditWords. EnableWindow (true); 
M_Send. EnableWindow (true); 
M_EditWords. SetFocus (); 
//
//ADD 
} 

//ADD 
LRESULT CP2PTalkerDlg: : OnReadMsg (WPARAM WPARAM, LPARAM LPARAM) 
{
//receiving messages from the other end system 
Cstrings STR, strHead, strData; 
The switch (WSAGETSELECTEVENT (lParam)) 
{
Case FD_READ: 
Socklen=sizeof (m_sockSelfRcvAddr); 
Recvfrom (SelfRcvSocket, (char *) & amp; Msgbuf, sizeof (msgbuf), 0, (LPSOCKADDR) & amp; M_sockSelfRcvAddr, (int *) & amp; Socklen); 
WSAAsyncSelect (SelfRcvSocket m_hWnd, WM_CLIENT_READCLOSE FD_READ); 
STR. The Format (" % s ", msgbuf MSG); 

//intercept packet header and data section 
Int n=STR. ReverseFind ('; '); 
StrHead=STR. Left (n); 
StrData=https://bbs.csdn.net/topics/str.Right (STR) GetLength () - (n + 1)); 
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