how to use keepalive commands during large file transfers

Giganews Newsgroups
Subject: how to use keepalive commands during large file transfers
Posted by:  Lucky Luciano (ali…@cyber-colony.net)
Date: Tue, 7 Feb 2006

HI,

I have the classic problem: cannot upload large files (>1gb) with tidftp.
After reading the posts I think the control channel is closed because of
inactivity, so my ftp waits some hours after the upload and the fires an
exception.

My code is simple as possible:

    try
        myftp.Put(sourcefile, destfile);
    except
        ;
    end;

Actually the file is uploaded 100%, but I think in the meantime the control
channel is closed, my ftp server's log says: file received ok, connection
closed.

Question1: what is best way to handle this error? I mean if the file is
uploaded should I reconnect, and check it?

Question2: how to keep the control channel alive with the NOOP command (ex.
every 90sec)? there is an event for this when tidftp is
uploading/downloading a file?

Question3: it is possible to test this in a local network? i cannot
reproduce this error with local servers (always ok), only with slower
internet connections.

Thanks,
LL

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