The PK program can be used to PeeK at the input and output buffers of
any terminal, and the line editor buffer of a display.  To run PK, give
the monitor command "R PK".  PK will ask for a terminal line number, and
will display that terminal's buffers plus the who line of the job, if
any, using that terminal.  PK can also display the contents of some of
the internal system variables associated with the terminal (see + and -
commands below; the default is not to display this system data).

If the selected terminal is hidden (by ESC H), PK will so notify you.
You may choose to override the hiding, but if so, the selected terminal
is notified that you are spying on it.

If you are using a SAIL display, the selected terminal's buffers will
be displayed on your screen about once per second, like a WHO display.
If you are using a non-display, the PK information will be typed once.

While PK is running on a display, you can give it any of the commands in
the table below to have it display different information (in the table,
<cr> means carriage return).  Whenever PK exits on a DD or III, the last
buffer display will remain on your screen until you reset your display
by BREAK P or by running another program.

<line number><cr>  Display buffers of the given terminal line.
+<line number><cr> Display given terminal line and enable data display.
-<line number><cr> Display given terminal line and disable data display.
    <linefeed>	   Display buffers of the next higher numbered terminal.
     <altmode>	   Display buffers of the next lower numbered terminal.
     αβ<digit>     Update the display NOW and every <digit> seconds (1:9).
        αβ0	   Update the display NOW, then only once for each command.
       +<cr>	   Enable display of system internal data at top of screen.
       -<cr>	   Disable display of system internal data at top of screen.
	<cr>	   Stop the displaying and exit to the monitor.
   <monitor cmd>   Exit and execute the given monitor command.

Do HELP PPK for information on a related "spy" program.