Execute a Console Application From VC++

Introduction

To Execute a Console Application From VC++ and retrieve the messages shown in the console.

In many situations we may need to execute a console application or a DOS application from within our MFC application. ShellExcecute can be used for this purpose, but can only be used to run the application. Messages shown in the console is not reachable. In such cases the following procedure can help.

Here we create a read write pipe (two separate pipes, one for reading and one for writing).

Then we use CreateProcess to execute the process. Createprocess must be supplied with pointers to variables of STARTUPINFO and PROCESS_INFORMATION structures.

The pipes created are assigned to STARTUPINFO structure before it is passed to the CreateProcess function.

The CreateProcess function is used to run a new program.

CreateProcess( 
        LPCWSTR lpszImageName, 
        LPCWSTR lpszCmdLine, 
        LPSECURITY_ATTRIBUTES lpsaProcess, 
        LPSECURITY_ATTRIBUTES lpsaThread, 
        BOOL fInheritHandles, 
        DWORD fdwCreate, 
        LPVOID lpvEnvironment, 
        LPWSTR lpszCurDir, 
        LPSTARTUPINFOW lpsiStartInfo, 
        LPPROCESS_INFORMATION lppiProcInfo);

• lpszImageName

  Pointer to a null-terminated string that specifies the module to execute.

• lpszCmdLine

  Pointer to a null-terminated string that specifies the command line to execute. The system adds a null character to the command line, trimming the string if necessary, to indicate which file was actually used.

The function ExecuteExternalFile, takes two arguments:

1. the application to be executed.
2. the arguments.

It executes the application and returns the messages that are printed into the console as a CString.

CString ExecuteExternalFile(CString csExeName, CString csArguments)
{
  CString csExecute;
  csExecute=csExeName + " " + csArguments;
  
  SECURITY_ATTRIBUTES secattr; 
  ZeroMemory(&secattr,sizeof(secattr));
  secattr.nLength = sizeof(secattr);
  secattr.bInheritHandle = TRUE;

  HANDLE rPipe, wPipe;

  //Create pipes to write and read data
  CreatePipe(&rPipe,&wPipe,&secattr,0);
  //
  STARTUPINFO sInfo; 
  ZeroMemory(&sInfo,sizeof(sInfo));
  PROCESS_INFORMATION pInfo; 
  ZeroMemory(&pInfo,sizeof(pInfo));
  sInfo.cb=sizeof(sInfo);
  sInfo.dwFlags=STARTF_USESTDHANDLES;
  sInfo.hStdInput=NULL; 
  sInfo.hStdOutput=wPipe; 
  sInfo.hStdError=wPipe;
  char command[1024]; strcpy(command,  
          csExecute.GetBuffer(csExecute.GetLength()));

  //Create the process here.
  CreateProcess(0 command,0,0,TRUE,
          NORMAL_PRIORITY_CLASS|CREATE_NO_WINDOW,0,0,&sInfo,&pInfo);
  CloseHandle(wPipe);

  //now read the output pipe here.
  char buf[100];
  DWORD reDword; 
  CString m_csOutput,csTemp;
  BOOL res;
  do
  {
                  res=::ReadFile(rPipe,buf,100,&reDword,0);
                  csTemp=buf;
                  m_csOutput+=csTemp.Left(reDword);
  }while(res);
  return m_csOutput;
}

Hope this code will be useful for you.