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C00002 00002	This writeup attempts to explain the privacy, spying, and mapping
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This writeup attempts to explain the privacy, spying, and mapping
features of the system.


PRIVACY

A user can request privacy for his TTY line, no matter what kind
of terminal he is on.  The command ESCAPE H (and the monitor
command TTY ESCAPE H) sets the privacy flag for your TTY line.
BREAK H (and TTY BREAK H) clear the privacy flag.  When the
privacy flag is set, the system (and soon certain system
programs) will NORMALLY not allow anyone to spy on your line.
Furthermore, anyone spying on your line when ESCAPE H is typed
will be stopped from doing so.

The state of the privacy flag for any TTY line can be retrieved
with the TTYSET UUO, function 20 (octal).  The (soon to be made
public) system programs that spy on TTY lines will use this UUO
to decide when they shouldn't spy unless asked to ignore privacy.

The privacy flag of an available line is always off.


OVERRIDING PRIVACY

PRIVACY IS NEVER GUARANTEED!  The privacy flag can be overridden
by a spy who explicitly asks to do so.  However, even such a spy
is stopped from spying on your TTY line (at least momentarily)
whenever you type ESCAPE H (although he can then ask again to
override the privacy flag).


RESPONSIBLE TERMINALS

THE TERMINAL RESPONSIBLE FOR A PRIVATE TTY LINE IS NEVER
OBSTRUCTED FROM SEEING THE PRIVATE TTY LINE.  The responsible
terminal is defined to be the last physical terminal that typed a
characters (while mapped) to the logical TTY line.

No one is responsible for an unused TTY line, unless the line
is a DD in the DD channel wait queue, in which case the DD
keyboard that put it there is responsible.


SPYING ON DATA DISC LINES AND CHANNELS--MAGIC COMMANDS

Most of the DD mapping, tying and video commands (explained in
KBDMAP.ME[UP,DOC]) can be given with a special version of ESCAPE
to override privacy requests.  This special version shall be
called MAGIC for short.  Normal ESCAPE and BREAK commands observe
privacy requests, but MAGIC commands do not.  Thus you can map to
a private DD line by typing what we will call MAGIC # M, and you
can tie your DD to the DD map of a private DD with MAGIC # L.

NOTE: IT IS CONSIDERED A GRAVE VIOLATION OF ETHICS TO SPY ON
SOMEONE ELSE'S PRIVATE TTY LINE UNLESS YOU HAVE SOME VERY
COMPELLING REASON (for example, the guy whose line it is asks you
to look at it).  The MAGIC commands should therefore not be used
as a matter of habit.  People caught randomly spying on private
TTY lines will be censured (at least).  If you see someone
randomly spying on private lines, please point out that this is
not acceptable behavior; if he continues, bring this fact to the
attention of the "higher ups" (e.g., LES).

To get MAGIC, type CONTROL-META-TOP-UNSHIFT-BREAK instead of
ESCAPE or BREAK (being sure to turn off SHIFT-LOCK).  MAGIC
always executes the ESCAPE version of a command instead of the
BREAK version, except for the L command, where it does the BREAK
version (to tie your DD to the DD map of another DD line).  Thus
you CANNOT type MAGIC versions of the commands BREAK # S, BREAK #
T, and BREAK # A (this might change).

The commands that accept MAGIC in place of ESCAPE or BREAK are:

	ESCAPE # M
	BREAK # L 
	ESCAPE # S 
	ESCAPE # A
	ESCAPE # T
	ESCAPE [prg]


COMING SOON: SYSTEM PROGRAMS FOR SPYING

Soon, certain programs will be made public which allow spying on
any TTY line (especially non-DD lines or from non-DD terminals).
These programs will observe the privacy flags of TTY lines being
spied upon except when the user specifically asks to override
privacy.  As with the MAGIC commands, use of these programs to
override privacy without a valid reason is considered
unacceptable behavior.