Streaming a modified PDF form to a client (in memory) ?

Q: We are populating an AcroForm with data from the database (user has
provided data earlier in the workflow), and the intent is not to save
this PDF to file but rather stream it from memory. I understand that
to display this PDF to the user's browser we have to rasterize it.
Would this launch Acrobat Reader on the client side, or show purely as
an image? I want the browser to show this in Reader so they can access
Save/Print functions. How do I do that?
A: It seems that all you need is to fill a PDF form, then save the
document in memory, and stream the resulting document to the client.
For an example of how to save PDF in memory, please take a look at
PDFDocMemory sample project (