<2.2> TeleRaid: a remote debugging aid

The 1108 has no Raid debugger (since Raid is written in BCPL), but does
provide a low-level "TeleRaid" service when it would otherwise fall into
RAID.  When the machine is in TeleRaid, it can be debugged from another
machine, or in some cases the user can issue commands to continue or
break into the computation in limited ways.  1100s and 1132s can also
run TeleRaid.

Once a machine is in TeleRaid, then another may be used to debug it by
calling (TELERAID <host>), where <host> is the Pup name or number of the
machine running the TeleRaid server.  The function TELERAID  is not in
the standard loadup (but is in the FULL.SYSOUT loadup); to load it, you
must load the files READSYS.DCOM, RDSYS.DCOM, VMEM.DCOM, and
REMOTEVMEM.DCOM from <Lisp>Library>.  The  user interface for TELERAID
is similar to that of Raid; type ? for an enumeration of commands.

When the maintenance panel of an 1108 indicates a Lisp-induced halt,
pressing the UNDO key starts the TeleRaid server.  TeleRaid changes the
cursor to the TeleRaid cursor, takes over the ethernet controller and
keyboard, then waits for commands from either the Ether or the keyboard.
Keyboard commands are given by holding down the control key (or PROPS on
the standard Dandelion keyboard) and striking another key.  As you
strike a key, the cursor changes to give feedback about the command you
are about to execute; the command is executed when you let go of the
key, but if you let go of the command key first, the command is aborted.
The commands are as follows:

    ↑N - like Raid ↑N: continue the computation.
    ↑D - like Raid ↑D: do a HARDRESET.
    ↑B - cause a break underneath the error.
    ↑P - display the machine's Pup host number (decimal) in the
maintenance panel
	       (for remote debugging).

TeleRaid refuses to execute the "↑B" command if the user is executing in
a place (e.g., inside of a garbage collection) that would be dangerous
to allow a user break.

You can put  an 1100 or 1132 (Dorado or Dolphin) into TeleRaid server
mode by giving the "R" command to Raid and thus remotely debug it or
make use of TeleRaid's ↑B command (nothing corresponding to this command
is available in standard RAID).