The CAtlServiceModuleT::Start Function
When the service is run, _tWinMain calls CAtlServiceModuleT::WinMain, which in turn calls CAtlServiceModuleT::Start.
CAtlServiceModuleT::Start sets up an array of SERVICE_TABLE_ENTRY structures that map each service to its startup function. This array is then passed to the Win32 API function, StartServiceCtrlDispatcher. In theory, one EXE could handle multiple services and the array could have multiple SERVICE_TABLE_ENTRY structures. Currently, however, an ATL-generated service supports only one service per EXE. Therefore, the array has a single entry that contains the service name and _ServiceMain as the startup function. _ServiceMain is a static member function of CAtlServiceModuleT that calls the non-static member function, ServiceMain.
Note
Failure of StartServiceCtrlDispatcher to connect to the service control manager (SCM) probably means that the program is not running as a service. In this case, the program calls CAtlServiceModuleT::Run directly so that the program can run as a local server. For more information about running the program as a local server, see Debugging Tips.