JSYS 666

[Duty Calls]

I've never told this story to anyone before. It's been about
thirty years, and I've decided to share it here.

Long ago, in a land far away...

I worked for a very large engineering company. My group had four
TOPS-20 machines, and we were starting to get some of those new
VAX boxes. I was the senior software person in charge of the 20s.

My immediate supervisor barely rose to the level of a pointy-haired
boss (PHB), but the group's manager was a technical person who had
even written a program that enjoyed some minor acclaim and use
within the company. He kept my supposed superior in check and I
had free reign to come and go as I pleased, as long as things were
running and the work got done.

As is often the case in big companies, there was a re-organization
and the manager got promoted. His position was filled from
outside the group with a non-technical manager who had a decidedly
bean-counter point of view. He held one-on-one meetings with each
of the staff, and when my turn came he wanted to know why I didn't
arrive at work each day at 8 a.m. like everyone else. Never mind
that I often stayed late, and dialed-in from home in the evenings
and on weekends. He made it clear that he expected me to keep
regular hours like everyone else.

I knew then that my time there was limited, and took what I felt
was appropriate action. The TOPS-20 monitor includes table space
for 511 (777 octal) JSYSes (system calls), even though not all of
them are used. I picked one of the unused slots -- number 666 --
and added a very simple patch to our site's TOPS-20 systems that
did a SETOM (set to ones) of the running job's capability word --
in effect, giving the user full privileges.

Soon enough, I fell afoul of the new regime and my supervisor,
emboldened by the new and equally technically incompetent manager,
took away my WHEEL privileges. Or so he thought.

TOPS-20 has a feature that links the terminal output buffers of
two jobs so that one can see what the other is doing. Normally
this requires the assent of the linked-to job, but a job with
privileges can simply create the link, and can do so without any
notice -- in effect, spying on the other job. An unprivileged
user cannot stop this, but a privileged user can detect the link
before it is made and be warned. Turn-key programs existed to
both create these spy links and detect them.

Each morning I would log in, jump into DDT, and execute JSYS 666.
Then I would run the spy detection program. Just about everyone
in the department used a VT100. I had been offered one as well,
but I preferred the VT52 keyboard and kept it instead. The escape
sequences for the two terminals are not compatible.

With some regularity, my supervisor would try and spy on me. I
would get the warning message, and then immediately jump into
EMACS, where I moved the cursor all around the screen. This would
result lots of garbage being displayed on a VT100, and eventually
it would lock up. A couple of cubicles away, I would hear my
supervisor mutter under his breath, and then power-cycle his
terminal. He never was successful in spying on me.

During this time, the manager of another department with a TOPS-20
system visited us, and for some reason they needed a copy of the
monitor. He took the one with the JSYS 666 patch. I wonder how
many machines around the company ended up with my little hack.

Fortunately, my job-hunting efforts paid off quickly, and I soon
landed a better position somewhere else.