Words about mux:

The default layer program is much like a jim frame (in time, jim will become
similar to the default layer program).  The select/cut/paste/snarf business
is exactly the same, and all layers share a single snarf buffer (which is,
for now, distinct from jim's).  The 'send' button2 menu operator sends the
selected text to unix.  If no text is selected, the contents of the snarf
buffer are sent.  Experiment to see how it all works; preloading the snarf
buffer with a commonly-executed command for the shell or whatever is
convenient.

The behaviour of typing and editing needs some explanation.  There is a point
in each layer, called the 'unix point', that is the character position where
the next character from unix will be inserted.  Unlike on a regular terminal,
this point is not advanced as you type characters, but only when you type
a newline.  Therefore, shell prompts and the like will appear at the beginning
of your half-typed line if you type ahead.

All text on the screen can be edited.  Typing a newline after the unix point
sends to unix the characters from the unix point to the newline.  At no
other time are characters sent to unix (but see the discussion of raw mode
below).  Therefore you can edit partially typed lines or copy text from
elsewhere on the screen.   To compose a mail message, simply type it
before the unix point and you can edit it as in jim.  Learn to re-use
what's on the display rather than retype.

Raw mode and no-echo are different: the unix point advances with each character
typed after it.  This makes dcon somewhat uncomfortable; someday dcon (not the
blit) may be fixed.

The terminal doesn't scroll as text is received or typed.  You must use the
scroll bar, which is much like jim's, or use the NO SCRL key which advances
a half page.  If you must have scrolling, and don't mind if it's slow,
there is a button 2 toggle that enables a poor facsimile of automatic
scrolling.
