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POWhy can I not acquire the keyboard with DirectInput?
 

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  1. POWhy can I not acquire the keyboard with DirectInput?
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    <p>I just started getting into DirectInput today, using DirectInput8 with <a href="http://nuwen.net/mingw.html" rel="nofollow">MinGW</a> on Windows 7 Ultimate N. I started off with a simple program to report which keys are currently down every second (just codes, not readable keys). However, I can't even get as far as acquiring the keyboard before it errors out:</p> <pre><code>#define _WIN32_WINNT 0x0601 #include &lt;dinput.h&gt; //link to dinput8.lib and dxguid.lib int main() { IDirectInput8 *dinput; DirectInput8Create(GetModuleHandle(nullptr), DIRECTINPUT_VERSION, IID_IDirectInput8, (void **)&amp;dinput, nullptr); IDirectInputDevice8 *kb; dinput-&gt;CreateDevice(GUID_SysKeyboard, &amp;kb, nullptr); kb-&gt;SetDataFormat(&amp;c_dfDIKeyboard); kb-&gt;SetCooperativeLevel(GetConsoleWindow(), DISCL_FOREGROUND | DISCL_NONEXCLUSIVE); kb-&gt;Acquire(); //fails with DIERR_INVALIDPARAM } </code></pre> <p>I omitted error checking, but what happens is that every call succeeds (by judgement of the <code>FAILED</code> macro) up to <code>Acquire()</code>. That call fails with the error <code>DIERR_INVALIDPARAM</code>. I looked on the MSDN pages and across the web, but I can't find any reason it would fail with that based on everything before it present and working.</p> <p>For good measure, I also tried looping the <code>Acquire()</code> call until it succeeded and then played around with windows and the keyboard while it was running, but the program never successfully acquired the keyboard in all the time it was running. How can I successfully acquire the keyboard?</p>
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    1. USchris
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    1. COJust FYI, Microsoft discourages use of DirectInput. It's basically an overengineered wrapper around Win32 raw input, whose main effect is to spawn a few unnecessary threads, and introduce a bit of overhead. If you want to handle keyboard or mouse input at this level, just use the raw input API
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      1. POWhy can I not acquire the keyboard with DirectInput?
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    2. CO@jalf, I was planning on eventually detecting Motioninjoy PS3 controller input for my own purposes :) The keyboard is the first part of many tutorials, so I decided to at least get it working before going all-out.
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