From: F. Petri on

I have an vxWorks FTP server running. I want to transfer a file to
that server, but before transfering it I want to check if the file
already exists, so the user can decide whether he wants to overwrite
the file.

I use CFtpFileFind to check if the file on the server alredy exists.
Then I use CInternetFile to open the file, and write it on the server.

This sometimes works, but sometimes CInternetFile::Open throws an
CInternetException with m_dwError = 12003 ("The server returned
extended information") and CInternetFile::GetErrorMessage returns "200
Type set to I, binary mode 200 Port set okay 426 Data connection
error"). The MSDN states that 12003 does not necessarily mean an
error, but the file is not created properly.

The code below is to demonstrate the problem (in a reproducable way).
The loop is necessary because the first 8 (or so) times everything
runs fine, but then the exception is thrown.

When the exception occurs, it does not help to shut down
CInternetSession and CFtpConnection and set them up again and try to
transfer the file again!

The problem does not occur if
- I use an Windows FTP server
- I do not use CFtpFileFind

Any help, however little, would be greatly appreciated.

void CMyDialog::OnButtonFTPTransfer()
CInternetSession *pINetSession;
CFtpConnection *pFtpConnection;

pINetSession = new CInternetSession(NULL, 1,
pFtpConnection = pINetSession->GetFtpConnection(""); // a
vxWorks FTP server

char buffer[1000] = "This data will be written to the file";
int n;

for (n = 0; n < 20; n++)
CFtpFileFind aFind(pFtpConnection);
CInternetFile *pIFile;

// if the following two lines are removed, the program runs

pIFile = pFtpConnection->OpenFile("file.txt", GENERIC_WRITE);
pIFile->Write(buffer, 37);

catch (CInternetException *pEx)
DWORD d = pEx->m_dwError;
AfxMessageBox("Exception caught");



delete pFtpConnection;
delete pINetSession;