I am looking for the very same information. I basically need to have my script capture some parameters that are included in the response text of a request. These are hidden form parameters that are tied to a given session, and so they can not be hard-coded in my program

Then I need to put those parameters into variables to formulate the script's next request.

The purpose for this part of my program is that it needs to authenticate to a site that uses two factor authentication. I can get my script to pass credentials properly. For the next step, I am trying to get it to "click" a link that sends a push notification to a mobile device. It is that link that has session parameter attributes, which must be passed along with it.

So if anyone knows a solution for this situation, I am also very keen to learn about it. :)