Using the Console Like MSDEV

Probably everybody who reads this article is familiar with msdev.exe. We know that if we type "msdev /?", we get usage information on the console. However, if we type "msdev", the IDE comes up. This dual behavior is achieved through an additional executable, called msdev.com. In this article you can find a fairly generic solution for adding the same capability to any kind of non-console program.

Click here for larger image

To use this functionality in your own non-console application, you have to
- call one function (see below) before making any calls that use the console and
- you will need to rename tester.com to "NAME_OF_YOUR_EXE.com".

Then, when you type NAME_OF_YOUR_EXE, the .com executable will start, create the framework needed to enable its console for the .exe and spawn the process. Here is how it works: Tester.com first creates the commandline that will be used to spawn the .exe process. It is done by replacing the .com extension with .exe and appending the rest of the command line arguments. Then, using the constructed command line, the new process is spawned in suspended mode. Then we create three named pipes, one for stdin, one for stdout and one for stderr. Three thread functions will serve as handlers on each pipe. The example below shows what the stdout pipe handler does:

void 
OutPipeTh(void* param)
{
 TCHAR buffer[1024];
 DWORD count = 0;

 ConnectNamedPipe(coutPipe, NULL);

 while(ReadFile(coutPipe, buffer, 1024, &count, NULL))
 {
  buffer[count] = 0;
  cout << buffer << flush;
 }
}

The .exe program needs to call a function at the beginning of its execution in order to establish connection with the pipes created by the .com application. The function is as follows:

BOOL InitializeDualMode(BOOL initMode)
{
 BOOL rc = FALSE;
 TCHAR szOutputPipeName[256];
 TCHAR szInputPipeName[256];
 TCHAR szErrorPipeName[256];

 // construct named pipe names
 //
 _stprintf( szOutputPipeName, 
 _T("\\\\.\\pipe\\%dcout"),
 GetCurrentProcessId() );

 _stprintf( szInputPipeName, 
 _T("\\\\.\\pipe\\%dcin"),
 GetCurrentProcessId() );

 _stprintf( szErrorPipeName, 
 _T("\\\\.\\pipe\\%dcerr"),
 GetCurrentProcessId() );

 // attach named pipes to stdin/stdout/stderr
 //
 rc = _tfreopen( szOutputPipeName, "a", stdout ) != NULL &&
 _tfreopen( szInputPipeName, "r", stdin ) != NULL &&
 _tfreopen( szErrorPipeName, "a", stderr ) != NULL;


 // if unsuccessful, i.e. no console was available
 // and initmode specifiec that we need to create one
 // we do so
 //
 if ( !rc && initMode)
 {
  rc = AllocConsole();
  if (rc)
  rc = _tfreopen( _T("CONOUT$"), "a", stdout ) != NULL &&
  _tfreopen( _T("CONIN$"), "r", stdin ) != NULL &&
  _tfreopen( _T("CONERR$"), "a", stderr ) != NULL; 
 }

 // synchronize iostreams with standard io
 //
 if ( rc )
  ios::sync_with_stdio();

 return rc;
}

Acknowledgements

Downloads