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c#.netwindows-xpacpiwinapi

C#: How to wake up system which has been shutdown?


Is there any Win32 API for waking up a system that has been shut down, at a specific time? I have seen a program named Autopower On which is able to power the system on at a specified time.


Solution

  • Got the below post from a site. Any body tried this?

    Nothing in the framework, so you'll have to "PInvoke" a bit. The API's you need to call are CreateWaitableTimer and SetWaitableTimer. Following is a complete (Q&D) sample that illustrates how you can set a system to be awoken from sleep/hibernate using above Win32 API's. Note that here I'm setting a relative wakeup time of 300000000 nSecs. That means that the computer will wake-up (supposing he's asleep or hibernating) within 30 seconds after setting the timer. Consult the MSDN docs for details on SetWaitableTimer and it's arguments.

    using System;
    using System.Runtime.InteropServices;
    using System.Windows.Forms;
    
    namespace Willys
    {
        class Program
        {
            [DllImport("kernel32.dll")]
            public static extern IntPtr CreateWaitableTimer(IntPtr lpTimerAttributes,
            bool bManualReset, string lpTimerName);
    
            [DllImport("kernel32.dll")]
            public static extern bool SetWaitableTimer(IntPtr hTimer, [In] ref long
            pDueTime, int lPeriod, IntPtr pfnCompletionRoutine, IntPtr
            lpArgToCompletionRoutine, bool fResume);
    
            [DllImport("kernel32", SetLastError = true, ExactSpelling = true)]
            public static extern Int32 WaitForSingleObject(IntPtr handle, uint
            milliseconds);
    
            static void Main()
            {
                SetWaitForWakeUpTime();
            }
    
            static IntPtr handle;
            static void SetWaitForWakeUpTime()
            {
                long duetime = -300000000; // negative value, so a RELATIVE due time
                Console.WriteLine("{0:x}", duetime);
                handle = CreateWaitableTimer(IntPtr.Zero, true, "MyWaitabletimer");
                SetWaitableTimer(handle, ref duetime, 0, IntPtr.Zero, IntPtr.Zero, true);
                uint INFINITE = 0xFFFFFFFF;
                int ret = WaitForSingleObject(handle, INFINITE);
                MessageBox.Show("Wake up call");
            }
        }
    }