Moving data between processes

Question

The reason I ask is that the widow does not support a good way of communicating between processes. Therefore, I want to create a DLL for the connection point between Windows processes. A thread belongs to a process and cannot be transferred to another process. Each thread has its own stack. If a DLL (loadlibray) is loaded and a DLL function is called that requests windows for memory. I am writing to think that a thread still belongs to the same process and allocates memory in the same process.

So, I think I can refer to the assembly to redistribute a small block of memory to another process. Create a critical section, copy the data to another (already created) memory block and return the original block to the original process with the window settings disabled. Someone has done this before. Or is this the best way.

Regards, Lex Dean

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I see other methods that heal quite quickly, but I need a very fast method that has a little overhead. Pipes and the Internet will obviously work, but not the best option, but easy to implement (thanks, to offer such suggestions guys). Sometimes I want to send several 500 byte blocks at fairly regular intervals. I like WM_COPYDATA because it looks fast, my biggest question I have looked around the internet is: GetCurrentProcess and DuplicateHandle to get a real handle. Search for another process. And using messages to configure memory, then use WM_COPYDATA. I need only two messages: a) pointer and size; b) the data has been copied. I easily process my GetCurrentProcess application process, with the exception of my pseudo descriptor,which is always equal to $ FFFFFFE. I need a real process descriptor, and no body on the Internet gives an example of a DuplicateHandle. This is what guarded me. Can you show me an example of a DuplicateHandle because I was about to be puzzled?

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Answer 1

IPC (interprocess communication) . ( . ). . .

http://www.cromis.net/blog/downloads/cromis-ipc/

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Answer 2

( ), / WM_COPYDATA: http://msdn.microsoft.com/en-us/library/ms649011(VS.85).aspx

, COPYDATASTRUCT:: lpData. , . . , . :

/* Both are conceptual windows procedures. */

/* For sending : */
{
    ...
    TCHAR msg[] = _T("This is a test\r\n");
    HWND target;
    COPYDATASTRUCT cd = {0};
    cd.lpData = _tcsdup(msg); // We allocate and copy a string, which is fine.
    cd.cbData = _tcsclen(msg) + 1; //The size of our data. Windows needs to know this.
    target = FindWindow(..); //or EnumProcesses
    SendMessage(target, WM_COPYDATA, (LPARAM)hwnd, (WPARAM)&cd);
}

/* For receiving */
{
    ...
    case WM_COPYDATA:
    {
        TCHAR* msg;
        COPYDATASTRUCT* cb = (COPYDATASTRUCT*)wParam;
        sender = FindWindow(..); //or EnumProcesses

        //check if this message is sent from the window/process we want
        if(sender == (HWND)lParam){
            msg = _tcsdup(cb->ldData);
            ...
        }
        break;
    }
}

.

Answer 3

Mailslots Delphi , .

Answer 4

"Win32 DLL . DLL DLL. DLL , :

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http://msdn.microsoft.com/en-us/library/h90dkhs0(VS.80).aspx

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Answer 5

Win32 . Windows IPC.

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Answer 6

, -: - DllMain , , . Thats, , .

 What I understand is when accessing a file, the internet scoket, and all thouse things. The DOS 640k memory block is used with the processors DS register. 

And the DLL allocates memory space in every process that calls loadlibray called dll. So, I think that: - since the memory space is used for dll, this space can be expanded and available for all processes.