Several questions about uploading shared media

media
media-upload
directmessages

#1

Hi, i’m working on app, that work with twitter api, and we want to implement new twitter direct messages for sending messages with attached media (images).

So, user can send same message for many users. And here I’m have a problem.
Twitter API documentation saying that I can upload chunk media with shared=true.

But I can’t find more information about that flag. Do I need set it only at INIT request when upload chunked media? It is Get parameter?

experimentally, I’m found that this flag not working with one request upload. I’m right?