reading files

This is a discussion on reading files within the C++ Programming forums, part of the General Programming Boards category; i have this code for reading files: Code: HANDLE h; h = CreateFile("D:\Dev-Cpp\Works\Updater\Client\abc\Client.exe", GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL); if(h ...

  1. #1
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    reading files

    i have this code for reading files:
    Code:
    HANDLE h;
    h = CreateFile("D:\\Dev-Cpp\\Works\\Updater\\Client\\abc\\Client.exe", GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
    if(h == INVALID_HANDLE_VALUE) Error("invalid handle");
    char buf[1024];
    DWORD w;
    ReadFile(h, buf, 1023, &w, NULL);
    Msg(buf);
    CloseHandle(h);
    and it works just fine with .txt files but not with .exe
    it prints me just 2 characters instead of 1023.
    is there another way to read it?

  2. #2
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    exe files don't contain text, they contain binary. The first 2 charactors of an exe file are zm (or mz I can't remember which order they are in) followed by zeros which means the zeros NULL terminate the string and so only the first 2 charactors are displayed.
    What are you trying to do with the exe file?

  3. #3
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    transfer it with winsock

  4. #4
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    TransmitFile()
    or look at the lpNumberOfBytesRead value (w) to see how much of the buffer was filled and send that much with send() (You would need to loop since the file is likely larger then 1023 bytes, also since this isn't text and you don't need to add a terminating zero you can use the full 1024 bytes for this.
    Last edited by Quantum1024; 05-21-2005 at 07:54 AM.

  5. #5
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    that's exactly what i do, but the new file only contains MZ
    maybe it's because i add the data to another string using sprintf and it adds only untill a null character?
    Last edited by hiya; 05-21-2005 at 08:08 AM.

  6. #6
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    Quote Originally Posted by hiya
    maybe it's because i add the data to another string using sprintf and it adds only untill a null character?
    That's what is happening. sprintf is a string function.

  7. #7
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    this should be in the windows programming board

  8. #8
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    oh sorry...
    when i send the data without sprintf, it sends all the data, but the client receiving only the first 3 characters and then nothing.
    how else can i send\receive the file except using transmitfile?

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