The filename is actually coming in in 2 places. The first is as part of the binary data 
Content-Disposition: form-data; name="mtdata"; filename="filename"
Content-Type: application/octet-stream
... binary data ...

[download]
The second is as a text field 
Content-Disposition: form-data; name="mtfilename"
filename

[download]

In reply to Re^2: Problem uploading file data using CGI by dougconran
in thread Problem uploading file data using CGI by dougconran

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