Lee Edward McMahon (October 24, 1931–February 15, 1989) was an American

computer scientist A computer scientist is a person who is trained in the academic study of computer science. Computer scientists typically work on the theoretical side of computation, as opposed to the hardware side on which computer engineers mainly focus (al ...

. __TOC__

Family and education

McMahon was born in

St. Louis St. Louis () is the second-largest city in Missouri, United States. It sits near the confluence of the Mississippi and the Missouri Rivers. In 2020, the city proper had a population of 301,578, while the bi-state metropolitan area, which e ...

Missouri Missouri is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it is bordered by eight states (tied for the most with Tennessee ...

, to father Leo E. McMahon and mother Catherine McCarthy. He grew up in

and attended St. Louis University High School. In 1955 he received his

bachelor's degree A bachelor's degree (from Middle Latin ''baccalaureus'') or baccalaureate (from Modern Latin ''baccalaureatus'') is an undergraduate academic degree awarded by colleges and universities upon completion of a course of study lasting three to six ...

summa cum laude Latin honors are a system of Latin phrases used in some colleges and universities to indicate the level of distinction with which an academic degree has been earned. The system is primarily used in the United States. It is also used in some Sou ...

from St. Louis University. McMahon was awarded a regular graduate fellowship from the St. Louis University for study in psychology at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

, where he then obtained a

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is a ...

psychology Psychology is the scientific study of mind and behavior. Psychology includes the study of conscious and unconscious phenomena, including feelings and thoughts. It is an academic discipline of immense scope, crossing the boundaries betwe ...

. His

thesis at

was published in 1963 with the title "Grammatical analysis as a part of understanding a sentence". He was married to Helen G McMahon, and they had two children, Michael and Catherine.

Bell Labs

McMahon worked for

Bell Labs Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...

from 1963 up until his death in 1989. He worked initially as a Linguistics Researcher and focussed around a language called FASE (Fundamentally Analyzable Simplified English) with the goal of improving communication between humans and computers. McMahon officially joined the

Computing Research Center in 1975. A project which attempted to clarify the authorship of

The Federalist Papers ''The Federalist Papers'' is a collection of 85 articles and essays written by Alexander Hamilton, James Madison, and John Jay under the collective pseudonym "Publius" to promote the ratification of the Constitution of the United States. The co ...

connected him to Robert Morris and began his involvement with early

Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and ot ...

development. McMahon is best known for his contributions to early versions of the

operating system, in particular the

sed sed ("stream editor") is a Unix utility that parses and transforms text, using a simple, compact programming language. It was developed from 1973 to 1974 by Lee E. McMahon of Bell Labs, and is available today for most operating systems. sed wa ...

stream editor. McMahon contributed to the development of

comm The command in the Unix family of computer operating systems is a utility that is used to compare two files for common and distinct lines. is specified in the POSIX standard. It has been widely available on Unix-like operating systems since ...

qsort qsort is a C standard library function that implements a polymorphic sorting algorithm for arrays of arbitrary objects according to a user-provided comparison function. It is named after the "quicker sort" algorithm (a quicksort variant due to R. ...

grep grep is a command-line utility for searching plain-text data sets for lines that match a regular expression. Its name comes from the ed command ''g/re/p'' (''globally search for a regular expression and print matching lines''), which has the sam ...

, index, cref, cu, and

Datakit Datakit is a virtual circuit switch which was developed by Sandy Fraser at Bell Labs for both local-area and wide-area networks, and in widespread deployment by the Regional Bell Operating Companies (RBOCs). Datakit uses a cell relay protocol simi ...

McMahon's system tournament

McMahon worked on the creation of a pairing system to go together with Bob Ryder of

in the early 1960s. The system was widely used in go tournaments - for example in the U.S. Championship tournaments of 1986.

References

Unix people Go (game) researchers Harvard University alumni American computer scientists 1931 births 1989 deaths {{US-compu-bio-stub