Josh Work U-Michigan MTS Michigan Terminal System: Anecdotes

There are a few amusing anecdotes that have been collected over the years.

Security and hacking

According to legend, several graduate-level Computer Science classes were given instructions to try to break into MTS. The few who succeeded in breaching the system security (mainly those who managed to obtain privileges beyond those of their normal user accounts) were given employment at the University's Computing Center. Their first task was to plug the security hole they found.

Problems with the date

In November of 1989, a minor itsy-bitsy bug was discovered in the MTS code. Nothing you'd call major, really. Seems that the United Kingdom-based MTS sites were having all sorts of file system-related problems. Luckily for us in the United States, we had 5 hours before it became midnight locally. The problem was that some of the file system code used an unsigned half-word integer (16 bits) to store the number of days since zero time (March 1, 1900). Unfortunately, the rest of the file system code used a signed half-word integer (15 bits data, 1 bit sign) — and when it became the 32,768th day after zero time, the sign bit flipped and parts of the system thought files were stamped as being created or modified 32,767 days in the future. MTS didn't like this concept, so it caused all sorts of system problems. (The change log comments are available.)

The systems programmers hurriedly patched the file system code to use unsigned half-word integers consistently, recompiled the operating system, and provided patches to the various MTS Consortium sites. (Hewlett-Packard was using a previous version of MTS — Distribution 5.1 instead of the then-current Distribution 6.0 — at one of their sites. We provided them with a binary-only version of the patch and informed them not to trust any previous backups of the operating system.)

Of course, as the senior programmer noted on the systems programmers' mailing list, this solution will only work until the 65535th day after zero time (which maps out to some time in 2061). His comment was that if anyone was still running what would in effect be a century-old operating system then that they got what they deserved. And besides, by 2061, all of the then-current systems programmers would be retired or deceased, so they really didn't much care. (Shades of the Year 2000 problem, huh?)

Destroying Godzilla

In MTS, the $DESTROY command was used to destroy (remove, delete) files. However, if you had a file named GODZILLA, you couldn't actually get rid of it in one step:

To remove this file, you had to $RENAME it first.

Spelling Lessons and More

Electronic mail was handled by the $MESSAGESYSTEM. Since the University of Michigan was (and still is) an institution of higher learning, $MESSAGESYSTEM insisted that you spell correctly. The $MESSAGESYSTEM command RETRIEVE was used to retrieve your messages from the master database. (Like cc:Mail and some other e-mail systems, each message was stored exactly once, and your mailbox contained pointers to those messages you sent or received. Once a message had 0 recipient-pointers and the Sunday evening purge rolled by, the message was removed from the system completely.) However, if you misspelled the command, you would be admonished:

 Didn't your momma ever tell you: I before E, except after C?

Unfortunately, in the very late 1980s, this feature was removed in the names of increasing friendliness to users. RETREIVE became a synonym in the $MESSAGESYSTEM command grammar for RETRIEVE. However, the *KERMIT program did correct your spelling well into the 1990s.

At one point, $MESSAGESYSTEM also provided lessons in polite conversation:

 Tsk, tsk, you'll never get to medical school with language like that.


You could ask the system for the time ($DISPLAY TIME), date ($DISPLAY DATE), or both ($DISPLAY TIMEDATE), and it would tell you. However, for people who had trouble with the concept of digital clocks, you could ask for it in analog:


There was a program on MTS called *PIZZAZDELIVERY that was ostensibly a way to order pizza delivery from several local merchants, using the "MTS dollars" you'd been alotted for CPU time to pay for it. It would go completely through an order process, and even print out a receipt. Many, many students waited in vain outside a computer site for their pizza...

(Submitted by Ray Ingles.)

Which Host on Halloween

While not strictly related to MTS, it is a Merit Network anecdote.

When you connected to the Merit computer network (the network of universities, colleges, and schools within the state of Michigan, connected to what was then known as CICNET in the Midwest; Merit was later known as MichNet), you received a Which Host? prompt. This was your instruction to enter the name of the remote host you wanted to connect to (such as UM for UM-MTS or UB for UB-MTS). On October 31st, however, in honor of halloween, the prompt was changed to Witch Ghost? (This was later scrapped as it caused automated scripts that looked for "Host?" to fail.)

Editor Fun

While in $EDIT mode, typing computer at the editor command prompt would elicit the response working!. This was actually documented, somewhere, as being there to test the operation of the edit mode command parser.

(Submitted by Jonathan Sell and Lyndon Nerenberg.)

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Last update Aug03/09 by Josh Simon (<>).