avr地方业务中有一个dba_bjldnw工具要在服务器上运行着.一旦断开业务即中止.需要写一个守护程序监视它,

一旦发现关闭了即重新启动.

为了防止守护程序本身被用户关闭,所以我打算做一个windows服务在后台运行.每5分钟列举一个当前系统进程,如果

没有发现dba_bjldnw.exe则重新启动.

问题是windows服务不是窗口进程,在这个进程中调用shellexecute打开的应用程序也是在后台运行,不能显示在当前窗口中.

后来搜索到可以在windows服务中打开窗口程序的方法.就是打开用户winsta0和desktop,取得和用户交互的权限后再打开窗口进程,果然可以在windows服务中打开窗口进程了:

  hinstance hprocesssnap = null;
 processentry32 pe32 = {0};

 //获取进程的内存镜照
 hprocesssnap = (hinstance) ::createtoolhelp32snapshot(th32cs_snapprocess,0);
 if(hprocesssnap == (handle) -1) return ;
 pe32.dwsize = sizeof(processentry32);

 dword flag = 0;
 cstring theprocssname = "dba_bjldnw.exe";

 //列举进程

 if(::process32first(hprocesssnap,&pe32)){
  do{
   if(!theprocssname.comparenocase(pe32.szexefile)){
    flag = 1;
    break;
   }
  }
  while(process32next(hprocesssnap,&pe32));
 }
 ::closehandle(hprocesssnap);

 if(!flag){ //如果没有找到

  hdesk   hdeskcurrent;
  hdesk   hdesk;
  hwinsta hwinstacurrent;
  hwinsta hwinsta;

  hwinstacurrent = getprocesswindowstation();

  if (hwinstacurrent == null){
   logevent(_t("get window station err"));
   return ;
  }

  hdeskcurrent = getthreaddesktop(getcurrentthreadid());
  if (hdeskcurrent == null){
   logevent(_t("get window desktop err"));
   return ;
  }

  //打开用户的winsta0
  hwinsta = openwindowstation("winsta0", false,                         
   winsta_accessclipboard   |
   winsta_accessglobalatoms |
   winsta_createdesktop     |
   winsta_enumdesktops      |
   winsta_enumerate         |
   winsta_exitwindows       |
   winsta_readattributes    |
   winsta_readscreen        |
   winsta_writeattributes);
  if (hwinsta == null){
   logevent(_t("open window station err"));
   return ;
  }

  if (!setprocesswindowstation(hwinsta)){
   logevent(_t("set window station err"));
   return ;
  }

  //打开desktop
  hdesk = opendesktop("default", 0, false,               
   desktop_createmenu |
   desktop_createwindow |
   desktop_enumerate    |
   desktop_hookcontrol  |
   desktop_journalplayback |
   desktop_journalrecord |
   desktop_readobjects |
   desktop_switchdesktop |
   desktop_writeobjects);
  if (hdesk == null){
   logevent(_t("open desktop err"));
   return;
  }

  setthreaddesktop(hdesk);  

  ::shellexecute(0,null,"f:\\ivrtj\\dba\\dba_bjldnw.exe",null,null,sw_maximize);
  cstring msg = "dba_bjldnw.exe 被重启动";
  logevent(msg);

  setprocesswindowstation(hwinstacurrent);
  setthreaddesktop(hdeskcurrent);
  closewindowstation(hwinsta);
  closedesktop(hdesk);
 } 

服务安装后一定要注意,右键->属性->登录,选择 本地系统帐户下面的允许服务与桌面交互打勾.