Add a binary file to an existing form, then post

Hello,
How can I add a binary file to a form that is loaded say via HTLoadtoChunk
then post that form ?
 
Essentially I wish to automate the posting of a local file via this form.
 
The form is .....
 
<form enctype="multipart/form-data"" method="POST" ACTION="/forms/Upload">
<input type="file" name="file"
<input type="submit" name="submit" value="submit">
</form>
 
I thought perhaps I need to create a HTAssocList from this form and then set
the value of "file" to my binary file
but not sure if I am on the right track ??
 
(environment is C UNIX solaris )
 
...regards 
Andrew Dodgshun
Developer
eiStream (Australia) Pty Ltd
http://www.eistream.com.au <http://www.eistream.com.au/> 
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