User`s guide

SET MODE
(KMON)
Sets or clears the obsolete FBMON$ bit in the configuration offset of the monitor
fixed area to indicate the obsolete SJ monitor characteristics (Only for compatibility
with RT–11 pre-version 5.6, user-written handlers that require the FBMON$ bit set
to OFF).
Format
SET MODE [NO]SJ
Condition
[NO]SJ
SET MODE SJ turns the FBMON$ bit off.
SET MODE NOSJ, the default, turns the FBMON$ bit on.
Description
RT–11, before Version 5.6, used the FBMON$ bit to distinguish between the removed
SJ monitor and the FB and XM monitors. Since RT–11 no longer supports the SJ
monitor, RT–11 no longer references that bit. By default, therefore, FBMON$ is set
to ON, and setting the bit to OFF is no longer a valid representation of the operating
system.
If you have a handler that checks the FBMON$ bit to make sure there is only one
user or to check for a condition other than where monitor data is located, then you
can issue the SET MODE SJ command before you install your handler. However,
after you install the handler, you should also issue the SET MODE NOSJ command
to prevent any program from accidentally thinking the SJ monitor is running the
operating system.
If you have a handler that checks the FBMON$ bit of the SJ monitor to determine
where monitor data is located, then your handler will not work on the FB, SB, XB,
ZB, XM, and ZM monitors.
For more information on the FBMON$ bit, (Bit 0) in the CONFIG Word, see the
RT–11 System Internals Manual.
250 RT–11 Command Descriptions