Thread: Retrieving the result of a third party application

Okay, I haven't been programming in C++ for a while, only C#. In C# htis was easy, but in C++ I have some problems...

I have a command line tool ( the Oracle SQLLdr in this case ) that I'd like to start and wait for. Works like a charm. However, I need to know if the started program terminated sucessfully. The Oracle documentation says the program will return 0 on success, other values for errors. Fine I thought, that's easy.

Code:

/// 
/// Calls the SQLLDR process to load the file
///
bool OracleTableLoadFile()
{
	if( ! CreateControlFile() )  return false;
	
	CString strParameters;
	
	strParameters.Format( _T("userid=%s/%s@%s control=%s.CTL data=%s bad=%s.BAD LOG=%s.LOG"),
						m_strUser, 
						m_strPassword,
						m_strDatasource,
						m_strOutput, 
						m_strOutput,
						m_strOutput,
						m_strOutput );

	SHELLEXECUTEINFO ExecuteInfo;

	memset(&ExecuteInfo, 0, sizeof(ExecuteInfo));

	ExecuteInfo.cbSize       = sizeof(ExecuteInfo);
	ExecuteInfo.fMask        = SEE_MASK_NOCLOSEPROCESS;                
	ExecuteInfo.hwnd         = 0;                
	ExecuteInfo.lpVerb       = _T("open");
	ExecuteInfo.lpFile       = _T("SQLLDR");
	ExecuteInfo.lpParameters = strParameters;
	ExecuteInfo.lpDirectory  = 0;
	ExecuteInfo.nShow        = SW_SHOW;
	ExecuteInfo.hInstApp     = 0;

	if( ! ShellExecuteEx( &ExecuteInfo ) )
	{
		Error( _T( "Unable to start sql loader" ) );
		return false;
	}

	WaitForSingleObject( ExecuteInfo.hProcess, INFINITE );



	return true;
}

However, I found no way to retrieve my started applications return value. Not with the structure I have, nor with the structures of CreateProcess or even the dreaded WinExec. WaitForSingleObject and all process starting functions only return their own success or failure.

How do I get the return value of my started app once it terminated ?

Help me Obi-Wan CBoard, you are my only help...

( I'm pretty sure the answer will be simple, so here's my next post in advance: "DOH ! Thank you, I will take a course in googling and reading comprehension as soon as possible " )

Edit:
I can use _tsystem( ... ) for this, but it's not really what I want to do...

[edit]
Down the bottom of the CreateProcess() documentation there is a link "Process and Thread Functions". Follow it and see what you find. Similar links are available for many winapi functions.
[/edit]

GetExitCodeProcess().

Call it after the process has completed(as indicated by WaitForSingleObject). CreateProcess() is generally preferred for starting a program over ShellExecute(Ex).

Remember to close ExecuteInfo.hProcess with CloseHandle() when you are done.
--

Code:

	SHELLEXECUTEINFO ExecuteInfo;

	memset(&ExecuteInfo, 0, sizeof(ExecuteInfo));

As a side note, there is a cleaner way to do this:

Code:

	SHELLEXECUTEINFO ExecuteInfo = { 0 };

Thanks a lot, that's what I was looking for !

Geez, I wish I could go back to C#