There are no streams in the traditional sense.  The cmd line output gets sent to the cursor location of a document being 
edited and by using cursor keys, text can be injected all over the document.  Sprites can be injected and are not serialized!   
Furthermore, the input can come from triggering macro widgets.  See Doc Overview and Doc Routines.

If you had a remote term and sent key Scan Codes, the user would press <CTRL-m> to access his Personal Menu to trigger his 
macros.  However, the local ~/PersonalMenu.DD might differ from the remote, causing loss of sync between local and remote 
sessions.   Also, the window size of local and remote might differ, so word-wrapped text would be different.    Injecting 
output text with different windows sizes would cause remote and local documents to not be in sync.

See Char Overview and Char Routines.

You can send characters into StdIn.  See In(), XTalk() and InFile.