Listing 1  
Listing 1: ServiceMain function  
void ServiceMain(int argc, char** argv) 
{ 
   int error; 
 
   ServiceStatus.dwServiceType = 
      SERVICE_WIN32; 
   ServiceStatus.dwCurrentState = 
      SERVICE_START_PENDING; 
   ServiceStatus.dwControlsAccepted   =  
      SERVICE_ACCEPT_STOP | 
      SERVICE_ACCEPT_SHUTDOWN;
   ServiceStatus.dwWin32ExitCode = 0; 
   ServiceStatus.dwServiceSpecificExitCode = 0; 
   ServiceStatus.dwCheckPoint = 0; 
   ServiceStatus.dwWaitHint = 0; 
 
   hStatus = RegisterServiceCtrlHandler(
      "MemoryStatus", 
      (LPHANDLER_FUNCTION)ControlHandler); 
   if (hStatus == (SERVICE_STATUS_HANDLE)0) 
   { 
      // Registering Control Handler failed
      return; 
   }  
   // Initialize Service 
   error = InitService(); 
   if (error) 
   {
      // Initialization failed
      ServiceStatus.dwCurrentState = 
         SERVICE_STOPPED; 
      ServiceStatus.dwWin32ExitCode = -1; 
      SetServiceStatus(hStatus, &ServiceStatus); 
      return; 
   } 
   // We report the running status to SCM. 
   ServiceStatus.dwCurrentState = 
      SERVICE_RUNNING; 
   SetServiceStatus (hStatus, &ServiceStatus);
 
   MEMORYSTATUS memory;
   // The worker loop of a service
   while (ServiceStatus.dwCurrentState == 
          SERVICE_RUNNING)
   {
      char buffer[16];
      GlobalMemoryStatus(&memory);
      sprintf(buffer, "%d", memory.dwAvailPhys);
      int result = WriteToLog(buffer);
      if (result)
      {
         ServiceStatus.dwCurrentState = 
            SERVICE_STOPPED; 
         ServiceStatus.dwWin32ExitCode      = -1; 
         SetServiceStatus(hStatus, 
                          &ServiceStatus);
         return;
      }
      Sleep(SLEEP_TIME);
   }
   return; 
}