:)

Yes, what I want is a header on my data due to an application layer protocol.

vikas amin wrote: Dont mind u can post your questions there is and open forum . I have a project awaiting for me in Modbus through serial , but its schelduled in Octomber 2005 .So if u can wait till then .... Nice Way to help other! thats what every one except from good programmer "Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow cheers, Alok Gupta VC Forum Q&A :- I/ IV

u mean the receiver after getting the data should say, "i got it"??that u've to code urself..;P V

Google is your friend. ;) http://www.modbus.org/toolkit.php[^] http://members.tripod.com/~mbserver/[^]

jyhguang wrote: I need to write a program that can send the data like what I have mention above It would help if someone (here) understood what you mentioned above. Before a receiver can know what it's expected to receive, it has to be told what to expect (or request the data itself). I assume that the destination command code(#) indicates the data type expected. In that case you should already have what you need. Just wondering, how many peaple here did you expect to know about: mewtocal OPC servers and PLCs? INTP Every thing is relative...

Like the other guy said, you're obviously lost at sea. Why would printf not work in a dialog app ? What were you using instead ? Christian Graus - Microsoft MVP - C++

1983ttj wrote: but the receive side is a Dos application, how do I design a dialog that I can receive and see the message I send? I repeat - the code in your DOS app will work in an MFC app. Christian Graus - Microsoft MVP - C++

What I mean is an interface that I can type my message and send it using TCP protocol and another interface to receive the message I type.

Its work! How do I change it so that I can type on the dos and send it. The code now is when I type what I want to send in this: char sendbuf[300] = " "; and after I compile, it will automatically send to the server. But what I want is when I compile it, I can type on it and then send it to the server.

I'm at a loss why you keep pasting all of this code here. I'd also reiterate that it's obvious that you're using code when you have no idea what it does. Copy and paste without examining the code is no way to learn. TTjen wrote: char sendbuf[300] = "Client: Sending data."; char recvbuf[300] = ""; bytesSent = send( m_socket, sendbuf, lstrlen(sendbuf), 0 ); As I said yesterday, it doesn't matter how big or small you make sendbuf, lstrlen will return the length of the string you assigned to it, which is 21. The rest of the variable just never gets sent, because it's beyond the null value which causes lstrlen to ( correctly ) stop counting. You can set this string to be any value you like, up to 300 characters, and it will send it and give you back it's length. A better approach would be to use a string class like std::string or, if you're using MFC, CString. Both give you access to the underlying char * without having to allocate any memory, or impose a length limit. then you can assign the text you type to this variable, and pass the buffer in to the send method. Christian Graus - Microsoft MVP - C++

i guess you are talking about a string formatting parameter, like into printf()... if so, %ld tells to the functions that a long decimal value is expected here... you should have a look at Format Specification Fields[^] and printf Type Field Characters[^] if not, please tell us a minimum because your are not clear at all... :sigh: TOXCCT >>> GEII power [toxcct][VisualCalc] -- modified at 5:58 Tuesday 6th September, 2005

Christian Graus wrote: Because the string you're passing in is that length, and you're passing in the result of strlen, which gives you that value. The length of the string he is sending is 21 (32 is the size of the array), I think that's why he is confsued when send returns 32? -- modified at 7:19 Tuesday 6th September, 2005 oh forget it, he really wonders why the string length is 21. :)

Tsaejen wrote: still cannot find a example program abuot server and single client. can somebody give me some example? Look at these example http://codersource.net/mfc_window_socket_programming_server.html http://codersource.net/win32_socket_client.html http://codersource.net/winsock_tutorial_server_select_model.html http://codersource.net/winsock_tutorial_server_event_model.html "Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow cheers, Alok Gupta VC Forum Q&A :- I/ IV

It accur more error. I think nevermind. The program that I edit have AfxBeginThread but I don't want it. But I cant confirm whether it correct or not. Below is the ListenThread and I just disable the AfxBeginThread. UINT ListenThread(LPVOID lParam) { HANDLE hThread; SOCKADDR_IN SktAddr; char szMessage[300]; ServerSkt = socket ( AF_INET, SOCK_STREAM, 0 ); if ( ServerSkt == INVALID_SOCKET ) { printf("Error INVALID_SOCKET 1\n"); } else { SktAddr.sin_family=AF_INET; SktAddr.sin_port=htons(6000); //SktAddr.sin_addr.s_addr=htonl(INADDR_ANY); SktAddr.sin_addr.s_addr=htonl("127.0.0.1"); if ( bind ( ServerSkt, ( LPSOCKADDR ) &SktAddr, sizeof ( SktAddr ) ) == SOCKET_ERROR ) { printf("Error INVALID_SOCKET 2\n"); } else { if ( listen ( ServerSkt, SOMAXCONN ) == SOCKET_ERROR ) { printf("Error INVALID_SOCKET 3\n"); } else { /*hThread=AfxBeginThread (AcceptThread,lParam,THREAD_PRIORITY_NORMAL); if ( hThread == NULL ) { wsprintf(szMessage, "(ListenThread) - AfxBeginThread() Error. Unable to Create AcceptThread() Thread."); WriteSysLog(szMessage); } else { wsprintf(szMessage, "(ListenThread) - AcceptThread() Thread Spinoff Completed Successfully."); WriteSysLog(szMessage); return 0; }*/ } } return 0; } } } return 0; } The AfxBeginThread have a AcceptThread, how do I simplify it if I don't want the AfxBeginThread? Below is the AcceptThread code: UINT AcceptThread ( LPVOID lParam ) { SOCKADDR_IN AddrFrom; int nAddrFromLen = sizeof ( AddrFrom ); SOCKETDATA* psktData; HANDLE hThread; char szMessage[300]; while (hHeap!=NULL) { psktData -> Skt = accept ( ServerSkt, ( LPSOCKADDR ) &AddrFrom, &nAddrFromLen ); if ( psktData -> Skt == INVALID_SOCKET ) psktData -> AddrFrom = AddrFrom; psktData -> nAddrFromLen = nAddrFromLen; psktData -> ParamPointer = lParam; hThread = AfxBeginThread ( ( AFX_THREADPROC ) ClientThread, ( LPVOID ) psktData, THREAD_PRIORITY_NORMAL, 0, 0, NULL ); if ( hThread == NULL ) { wsprintf(szMessage, "(AcceptThread) - AfxBeginThread() Error. Unable to Create ClientThread() Thread."); WriteSysLog(szMessage); HeapFree ( hHeap, 0, psktData ); closesocket ( psktData -> Skt ); break; } } return 0; }