PRB: ATL Service Run from the IDE Doesn't Log Events to Console

• The Microsoft Active Template Library (ATL), versions 2.0, 3.0, included with:
  • Microsoft Visual C++, 32-bit Editions, versions 5.0, 6.0

SYMPTOMS

Using the ATL COM AppWizard to generate an NT service may not produce code that behaves as expected. When the AppWizard-generated service is started as a local server, the message strings passed to CServiceModule::LogEvent() are not displayed to the console. When started as a service, the messages are logged into the applications' event log.

CAUSE

In the generated code CServiceModule::LogEvent() calls _putts() in to write the message to stdout, but stdout is not setup by default.

RESOLUTION

To remedy this behavior, the developer should do one of the following:

• Edit CServiceModule::Start() to initialize stdout as desired (that is, redirect it either to a console or to a file). The code to do this is in the More Information section below.
• Replace _putts() with ATLTRACE().
• Redirecting the output of the application to a file, in a console window. For example:
  
  MyApp.exe > output.txt
  
  
• In CServiceModule::LogEvent(), remove the "if" statement and _putts() statement, so that the output always goes to the application log file.

MORE INFORMATION

To correct this problem, the developer should edit CServiceModule::Start() as follows:

inline void CServiceModule::Start()
   {
       SERVICE_TABLE_ENTRY st[] =
      {
           { m_szServiceName, _ServiceMain },
           { NULL, NULL }
       };
       if (m_bService && !::StartServiceCtrlDispatcher(st))
       {
           m_bService = FALSE;
       }
       if (m_bService == FALSE)
       {
           // Allocate a new console.
           AllocConsole();
           // Redirect stdout to the console.
           freopen("CONOUT$", "wta+", stdout);
           Run();
           // Free the console.
           FreeConsole();
       }
   } 

Steps to Reproduce Behavior

1. Create a new project with ATL COM AppWizard. In step 1, specify Server Type as Service(EXE).



2. Build the project.



3. Execute the project either from the command line or from the IDE.
   
   Notice that the message "Service started" does not appear anywhere.



4. Make the changes outlined in the first resoultion.



5. Build and run.
   
   You'll notice a new console displaying the message "Service started."

Additional query words:

Keywords : kbATL200 kbATL210 kbService kbVC500 kbVC600 kbATL300 kbGrpMFCATL
Version : WINDOWS:2.0,3.0
Platform : WINDOWS
Issue type : kbprb