Real Checko's Blog: 糟糕的： CeRunAppAtEvent

只能說這真是一個/組莫名奇妙的api呀....

CE 可以用

CeRunAppAtEvent(_T("\\\\.\\Notifications\\NamedEvents\\MYWAKEUPEVENT"),
              NOTIFICATION_EVENT_WAKEUP

要求 kernel (GWES) 把 OS內部的 EVENT_WAKEUP 轉成 Signal MYWAKEUPEVENT。

但是...這個 funciton 被 call 幾次， wakeup 時，那個 event 就會被 signal 幾次。

也就是說，即使你的 ap 已經結束，但是event 已經 create 起來，OS也註冊了，所以即使你的 Ap 已經結束了，OS 還是會依照註冊的內容執行..

所以，要記得 un-register...就是把那個 event 改對應到 NOTIFICATION_EVENT_NONE 就可以：

CeRunAppAtEvent(_T("\\\\.\\Notifications\\NamedEvents\\MYWAKEUPEVENT"),
              NOTIFICATION_EVENT_NONE)

附上測試的 code :


// SYSWAKEUPEVENT.cpp : Defines the entry point for the application.
//

#include "stdafx.h"

#include <notify.h>


HWND MainWnd;
int rcvcnt=0;

DWORD WINAPI WaiterThread(PVOID pArg)
{
 HANDLE WakeUpEvent;

 WakeUpEvent = CreateEvent(NULL,FALSE,FALSE,_T("MYWAKEUPEVENT"));
 if(WakeUpEvent == NULL){
     RETAILMSG(1,(TEXT("CreateEvent Failed\r\n")));
     ExitThread(0);
 }

 if(!CeRunAppAtEvent(_T("\\\\.\\Notifications\\NamedEvents\\MYWAKEUPEVENT"),
     NOTIFICATION_EVENT_NONE)){
     RETAILMSG(1,(TEXT("CeRunAppAtEvent NONE Failed\r\n")));
     ExitThread(0);
 }


 if(!CeRunAppAtEvent(_T("\\\\.\\Notifications\\NamedEvents\\MYWAKEUPEVENT"),
     NOTIFICATION_EVENT_WAKEUP)){
     RETAILMSG(1,(TEXT("CeRunAppAtEvent Failed\r\n")));
     ExitThread(0);
 }

 while(1){
     DWORD EventGot;

     EventGot = WaitForSingleObject(WakeUpEvent,INFINITE);
     if(EventGot==WAIT_OBJECT_0){
         rcvcnt++;
         RETAILMSG(1,(TEXT("received! %d\r\n"),rcvcnt));
         InvalidateRect(MainWnd,NULL,TRUE);
     }else{
         RETAILMSG(1,(TEXT("receive not object 0 : %d\r\n"),EventGot));
     }
 }

}

HANDLE hWaiterThread;


LRESULT CALLBACK MainWndProc(HWND hWnd, UINT wMsg, WPARAM wParam, LPARAM lParam)
{
 PAINTSTRUCT ps;
 RECT rect;
 HDC hdc;

 switch(wMsg){
     case WM_PAINT:
         {
             TCHAR outtext[50];

             GetClientRect(hWnd,&rect);
             hdc = BeginPaint(hWnd, &ps);

             swprintf(outtext,TEXT("Received WAKEUP EVENT: %d"),rcvcnt);

             DrawText(hdc, outtext,-1,&rect,DT_CENTER | DT_CENTER | DT_SINGLELINE);
             EndPaint(hWnd,&ps);
         }
         return 0;
     case WM_DESTROY:
         if(hWaiterThread)
             CloseHandle(hWaiterThread);
         PostQuitMessage(0);
 }
 return DefWindowProc(hWnd, wMsg, wParam, lParam);
}

int WINAPI WinMain(HINSTANCE hInstance,
                  HINSTANCE hPrevInstance,
                  LPTSTR     lpCmdLine,
                  int       nCmdShow)
{
WNDCLASS wc;
MSG msg;

// register the main windows class
wc.style = 0;
wc.lpfnWndProc = MainWndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = NULL;
wc.hCursor = LoadCursor(NULL,IDC_ARROW);
wc.hbrBackground = (HBRUSH) GetStockObject(WHITE_BRUSH);
wc.lpszMenuName = NULL;
wc.lpszClassName = TEXT("SYSWAKEUPEVENT");

if(RegisterClass(&wc) == NULL){
    RETAILMSG(1,(TEXT("RegisterClass Failed\r\n")));
    return -1;
}

MainWnd = CreateWindowEx(WS_EX_NODRAG,TEXT("SYSWAKEUPEVENT"),TEXT("SYSWAKEUPEVENT"),
                     WS_VISIBLE | WS_CAPTION | WS_SYSMENU,
                     CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
                     NULL, NULL, hInstance, NULL);
if(!IsWindow(MainWnd)){
    RETAILMSG(1,(TEXT("CreateWindowsEx Failed\r\n")));
    return -2;
}

ShowWindow(MainWnd,nCmdShow);
UpdateWindow(MainWnd);

hWaiterThread = CreateThread(NULL,0,WaiterThread,NULL,0,NULL);
if(hWaiterThread == NULL){
    RETAILMSG(1,(TEXT("CreateThread Failed\r\n")));
}





while(GetMessage (&msg,NULL,0,0) ) {
    TranslateMessage(&msg);
    DispatchMessage(&msg);
}

return msg.wParam;


 return 0;
}