Not true. LSX was developed by yours truly during the mid-70's
while I was at Bell Labs in Murray Hill. See BSTJ July/August 1978,
page 2087-2101. It was developed to support some real-time
features like contiguous files and asynchronous I/O. A number
of groups in Bell Labs used LSX and added device drivers to
support their dedicated applications.

Western Electric (WE) was responsible for licensing the UNIX system
at the time and only provided source code for the UNIX system for
the PDP11 computer with an MMU for $20K. LSX source code
was not included in this.

I also developed (actually modified and wrote device drivers for)
a version of the UNIX system that ran on the PDP11/10 computer,
which also did not have an MMU. It could support up to four users.
I believe that the source code for this system (Mini-UNIX) was
provided to some universities by the UNIX Support group at
Bell Labs. WE did not license this.

I do not believe that WE ever considered licensing a binary
version of LSX or the UNIX System to run on the IBM PC or
any other microcomputer. WE only offered binary licenses
later on, and then only for the PDP11 with an MMU first.
In hindsight, a missed opportunity, but that's another story.

Doug may be able to offer some insight into this as well.

Thanks for asking,

Heinz Lycklama

On 2/21/2020 2:37 AM, Ed Bradford wrote:

I also worked with LSX - a stripped down version of Unix that required no MMU. It worked on a PDP 11/03 and we delivered an LSX product to the telco's based on LSX. My faulty memory tells me Mike Lesk created LSX. Is that true?

Did BTL/AT&T ever try to sell LSX to IBM for its 1981 intro of the IBM PC?

Ed Bradford, BTL 1976-1983

Columbus and Whippany