It is possible but the web browser does not allow it. Let me go over how the filename is derived and why it has to be associated with each file.
When doing an upload we have to allow for multiple files to be defined. This would be used if you have multiple file input types on an html form that the user can submit at once. The browser tells us about each file right before that file in the body of the data being sent. I have copied what the browser sends to us on a multi-file upload:
-----------------------------170062046428149\r\n
Content-Disposition: form-data; name="fileContent"; filename="myfile1.dat"\r\n
Content-Type: binary/octet-stream\r\n
\r\n
0xf0 0xf1 0xf2 0xf3 0xf4\r\n
-----------------------------170062046428149\r\n
Content-Disposition: form-data; name="fileContent"; filename="myfile2.dat"\r\n
Content-Type: binary/octet-stream\r\n
\r\n
0xf0 0xf1 0xf2 0xf3 0xf4\r\n
-----------------------------170062046428149\r\n
Content-Disposition: form-data; name="fileContent"; filename="myfile3.dat"\r\n
Content-Type: binary/octet-stream\r\n
\r\n
0xf0 0xf1 0xf2 0xf3 0xf4\r\n
-----------------------------170062046428149--\r\n
Because each file is defined by the browser as its being sent this limits how we name the file. You always have the option of creating the http upload headers yourself and setting the above filename in the Content-Disposition. Since this is just a side effect of the protocol and allowing the client to work on their own there isn't much you can do.
Please let me know if this is not clear.
Regards,
Barry R.