Talking w/ hardware

This is a discussion on Talking w/ hardware within the C++ Programming forums, part of the General Programming Boards category; I was wondering how to send/receive signals to and fo hardware with c++? I'm not asking for a complete description, ...

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    Talking w/ hardware

    I was wondering how to send/receive signals to and fo hardware with c++? I'm not asking for a complete description, just a phrase that I can search google with to get a tutorial on this subject. The subject being, for instance, how to code for one program to tell another program that the 'P' button on the keyboard has been pushed or that the mouse was moved up y and over x, when the keyboad 'P' or mouse was never physically touched. Thanks for your advice in advance.

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    Cat without Hat CornedBee's Avatar
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    There is no mechanism in C++ that offers port input and output. The usual way is inline assembly.
    It is possible to write interrupt handlers partially in C/C++. But installing them is still likely to require some assembly.

    However, modern OSs (Linux, Windows) will disallow this direct communication with the hardware.
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    Code Goddess Prelude's Avatar
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    >I was wondering how to send/receive signals to and fo hardware with c++?
    Code:
    cout<<"Hello, world!"<<endl;
    My best code is written with the delete key.

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    How do bots work then if you can't directly send to the hardware?

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    API calls

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    It's full of stars adrianxw's Avatar
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    With Windows, you can get a handle to a port with the CreateFile() API function. Once you have a handle, you can use the handle based I/O routines.
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    Lightbulb Let's pretend you're running windows... PostMessage()

    Ah, I think I found it: PostMessage() sends a "message" to the Window.

    How Windows Programs Work: Each windows application runs a loop which checks for messages from the operating system. For example, when you press the left mouse-button down, the operating system sends a WM_LBUTTONDOWN message to the message queue.

    Note that sumulating a key-press or mouse-click does not require accessing hardware (on a Windows system). It's done through the OS.

    Windows programming is not that easy. Here's a Windows tutorial. You'll need to at least know how to get a handle to the target window, and you'll need to look-up the WM_ messages.

    [EDIT] -
    If you want an easy (Not C/C++) way of automating clicks & keystrokes, check-out WinBatch. I've used WinBatch to automate stuff that had to be run nightly.
    Last edited by DougDbug; 01-10-2005 at 03:49 PM.

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