Some sites have forms which are Flash.
How can I programmatically, fill out these forms ?
Is the only solution sending POST via cURL by first monitoring the http headers being sent ?
That would only work if the form you're filling out is sending back the results with a POST. There's many different ways for Flash/Flex forms to pass back the data, using http, web services, rpc or even sockets.
Ideally, you need to decompile the swf (which can be done automaticaly), and within the decompiled source you will be able to see the forms and automatically fill them.
To do so, you will need:
You may want to check something on google, or there: http://freemovie.sourceforge.net
Hope it helps!
I imagine there are ways you could automate a series of commands like typing in a field, hitting tab, typing, tabbing etc., but to achieve the end result of submitting the information to the server it probably would be faster and easier to just submit the HTTP POST using a tool like cURL.