Console i/o redirection

[death_oclock]

I'm writing a program that opens another console application with redirected input and output handles. I don't get any errors when I run this, but the console closes immediately, despite the system("pause") at the end. With the current solution, I have it redirecting to files, but another solution using pipes (commented out) yielded the same results. Here is the relevant code:

edit: I should mention that hStdIn, hStdOut, hStdErr, and hChildProcess are globally defined handles.

BOOL createProcess(WCHAR commandLine[])
{
	//HANDLE hStdInRead;
	//HANDLE hStdInWriteTmp;
	//HANDLE hStdOutWrite;
	//HANDLE hStdOutReadTmp;
	//HANDLE hStdErrWrite;
	//HANDLE hStdErrReadTmp;
	SECURITY_ATTRIBUTES sa;
	STARTUPINFO si;
	PROCESS_INFORMATION pi;

	ZeroMemory(&sa, sizeof(SECURITY_ATTRIBUTES));

	/*sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	sa.bInheritHandle = TRUE;

	if(!CreatePipe(&hStdInRead,
				   &hStdInWriteTmp,
				   &sa,
				   0))
	{
		error(L"Failed to create stdin handle.");
		return FALSE;
	}

	if(!CreatePipe(&hStdOutReadTmp,
				   &hStdOutWrite,
				   &sa,
				   0))
	{
		error(L"Failed to create stdout handle.");
		return FALSE;
	}

	if(!CreatePipe(&hStdErrReadTmp,
			   &hStdErrWrite,
			   &sa,
			   0))
	{
		error(L"Failed to create stderr handle.");
		return FALSE;
	}

	// create non-inheritable duplicates of the handles

	if(!DuplicateHandle(GetCurrentProcess(),
						hStdInWriteTmp,
						GetCurrentProcess(),
						&hStdIn,
						NULL,
						FALSE,
						DUPLICATE_SAME_ACCESS))
	{
		error(L"Failed to duplicate stdin handle.");
		return FALSE;
	}

	if(!DuplicateHandle(GetCurrentProcess(),
						hStdOutReadTmp,
						GetCurrentProcess(),
						&hStdOut,
						NULL,
						FALSE,
						DUPLICATE_SAME_ACCESS))
	{
		error(L"Failed to duplicate stdout handle.");
		return FALSE;
	}

	if(!DuplicateHandle(GetCurrentProcess(),
						hStdErrReadTmp,
						GetCurrentProcess(),
						&hStdErr,
						NULL,
						FALSE,
						DUPLICATE_SAME_ACCESS))
	{
		error(L"Failed to duplicate stderr handle.");
		return FALSE;
	}

	// close inheritable pipes
	CloseHandle(hStdInWriteTmp);
	CloseHandle(hStdOutReadTmp);
	CloseHandle(hStdErrReadTmp);*/

	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	sa.bInheritHandle = TRUE;

	// try to create a new file first, if that doesnt't work open the existing one

	hStdIn = CreateFile(L"Input.txt",
						GENERIC_WRITE,
						FILE_SHARE_READ,
						&sa,
						CREATE_NEW,
						FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
						NULL);
	if(!hStdIn)
	{
		hStdIn = CreateFile(L"Input.txt",
							GENERIC_WRITE,
							FILE_SHARE_READ,
							&sa,
							TRUNCATE_EXISTING,
							FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
							NULL);
		if(!hStdIn)
		{
			error(L"Failed to create or open input file.");
			return FALSE;
		}
	}

	hStdOut = CreateFile(L"Output.txt",
						GENERIC_READ,
						FILE_SHARE_WRITE,
						&sa,
						CREATE_NEW,
						FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
						NULL);
	if(!hStdOut)
	{
		hStdOut = CreateFile(L"Output.txt",
							GENERIC_READ,
							FILE_SHARE_WRITE,
							&sa,
							TRUNCATE_EXISTING,
							FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
							NULL);
		if(!hStdOut)
		{
			error(L"Failed to create or open output file.");
			return FALSE;
		}
	}

	hStdErr = CreateFile(L"Error.txt",
						GENERIC_READ,
						FILE_SHARE_WRITE,
						&sa,
						CREATE_NEW,
						FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
						NULL);
	if(!hStdErr)
	{
		hStdErr = CreateFile(L"Error.txt",
							GENERIC_READ,
							FILE_SHARE_WRITE,
							&sa,
							TRUNCATE_EXISTING,
							FILE_ATTRIBUTE_NORMAL, //FILE_FLAG_DELETE_ON_CLOSE,
							NULL);
		if(!hStdErr)
		{
			error(L"Failed to create or open input file.");
			return FALSE;
		}
	}

	ZeroMemory(&si, sizeof(STARTUPINFO));
	ZeroMemory(&pi, sizeof(PROCESS_INFORMATION));

	si.cb = sizeof(STARTUPINFO);
	si.dwFlags = STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
	si.wShowWindow = SW_SHOW; //SW_HIDE;
	si.hStdInput = hStdIn;
	si.hStdOutput = hStdOut;
	si.hStdError = hStdErr;

	if(!CreateProcess(NULL,
					  commandLine,
					  NULL,
					  NULL,
					  TRUE,
					  NORMAL_PRIORITY_CLASS,
					  NULL,
					  NULL,
					  &si,
					  &pi))
	{
		error(L"Failed to create process.");
		return FALSE;
	}

	/*// close the child process' handles
	CloseHandle(hStdInRead);
	CloseHandle(hStdOutWrite);
	CloseHandle(hStdErrWrite);*/

	CloseHandle(pi.hThread);
	hChildProcess = pi.hProcess;

	return TRUE;
}

I can post the application it opens if necessary, but I doubt it would be. It works perfectly on its own.

[death_oclock]

I should also mention that if I leave out the STARTF_USESTDHANDLES flag in the STARTUPINFO structure, it works fine (except that, obviously, the i/o isn't redirected).

[death_oclock]

I solved this myself. I'm not sure why the file idea didn't work, but going back to the pipes idea, I just passed the console the wrong handles. For any others having the problem, make sure you give it the stdInRead handle, and the stdOutWrite and stdErrWrite handles.