Henry Spencer (born 1955) is a

Canadian Canadians () are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''C ...

computer programmer A programmer, computer programmer or coder is an author of computer source code someone with skill in computer programming. The professional titles ''software developer'' and ''software engineer'' are used for jobs that require a progr ...

and space enthusiast. He wrote "regex", a widely used

software library In computing, a library is a collection of resources that can be leveraged during software development to implement a computer program. Commonly, a library consists of executable code such as compiled functions and classes, or a library can ...

for

regular expression A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" ...

s, and co-wrote

C News C News is a news server package, written by Geoff Collyer, assisted by Henry Spencer, at the University of Toronto as a replacement for B News. It was presented at the Winter 1987 USENIX conference in Washington, D.C. Functionally, the operati ...

, a

Usenet Usenet (), a portmanteau of User's Network, is a worldwide distributed discussion system available on computers. It was developed from the general-purpose UUCP, Unix-to-Unix Copy (UUCP) dial-up network architecture. Tom Truscott and Jim Elli ...

server program. He also wrote ''The Ten Commandments for C Programmers''. He is coauthor, with David Lawrence, of the book ''Managing Usenet''. While working at the

University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university whose main campus is located on the grounds that surround Queen's Park (Toronto), Queen's Park in Toronto, Ontario, Canada. It was founded by ...

he ran the first active Usenet site outside the U.S., starting in 1981. His records from that period were eventually acquired by

Google Google LLC (, ) is an American multinational corporation and technology company focusing on online advertising, search engine technology, cloud computing, computer software, quantum computing, e-commerce, consumer electronics, and artificial ...

to provide an archive of Usenet in the 1980s. The first international Usenet site was run in

Ottawa Ottawa is the capital city of Canada. It is located in the southern Ontario, southern portion of the province of Ontario, at the confluence of the Ottawa River and the Rideau River. Ottawa borders Gatineau, Gatineau, Quebec, and forms the cor ...

, in 1981; however, it is generally not remembered, as it served merely as a read-only medium. Later in 1981, Spencer acquired a Usenet feed from

Duke University Duke University is a Private university, private research university in Durham, North Carolina, United States. Founded by Methodists and Quakers in the present-day city of Trinity, North Carolina, Trinity in 1838, the school moved to Durham in 1 ...

, and brought "utzoo" online; the earliest public archives of Usenet date from May 1981 as a result. The small size of Usenet in its youthful days, and Spencer's early involvement, made him a well-recognised participant; this is commemorated in Vernor Vinge's 1992 novel ''

A Fire Upon the Deep ''A Fire Upon the Deep'' is a 1992 science fiction novel by American writer Vernor Vinge. It is a space opera involving superhuman intelligences, aliens, variable physics, space battles, love, betrayal, genocide, and a communication medium re ...

''. The novel featured an interstellar communications medium remarkably similar to Usenet, down to the author including spurious message headers; one of the characters who appeared solely through postings to this was modeled on Spencer (and, slightly obliquely, named for him). He is also credited with the claim that "Those who do not understand Unix are condemned to reinvent it, poorly."

Preserving Usenet

In mid-December 2001, Google unveiled its improved Usenet archives, which now go more than a decade deeper into the Internet's past than did the millions of posts that the company had originally acquired when it bought an existing archive called

Deja News Google Groups is a service from Google that provides Internet forum, discussion groups for people sharing common interests. Until February 2024, the Groups service also provided a gateway to Usenet newsgroups, both reading and posting to them, vi ...

. Between 1981 and 1991, while running the zoology department's computer system at the University of Toronto, Spencer copied more than 2 million Usenet messages onto magnetic tapes. The 141 tapes wound up at the

University of Western Ontario The University of Western Ontario (UWO; branded as Western University) is a Public university, public research university in London, Ontario, Canada. The main campus is located on of land, surrounded by residential neighbourhoods and the Thame ...

, where Google's Michael Schmidt tracked them down and, with the help of David Wiseman and others, got them transferred onto disks and into Google's archives.

Free software contributions

Henry Spencer helped Geoff Collyer write

in 1987. At around the same time he wrote a non-proprietary replacement for regex(3), the

Unix Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user 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, a ...

library for handling

regular expressions A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of character (computing), characters that specifies a pattern matching, match pattern in string (computer science), text. Usually ...

, and made it freely available; his API followed that of Eighth Edition

Research Unix Research Unix refers to the early versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). The term ''Research Unix'' first app ...

. Spencer's library has been used in many software packages, including

Tcl TCL or Tcl or TCLs may refer to: Business * TCL Technology, a Chinese consumer electronics and appliance company ** TCL Electronics, a subsidiary of TCL Technology * Texas Collegiate League, a collegiate baseball league * Trade Centre Limited ...

MySQL MySQL () is an Open-source software, open-source relational database management system (RDBMS). Its name is a combination of "My", the name of co-founder Michael Widenius's daughter My, and "SQL", the acronym for Structured Query Language. A rel ...

(prior to MySQL 8.0.4), and

PostgreSQL PostgreSQL ( ) also known as Postgres, is a free and open-source software, free and open-source relational database management system (RDBMS) emphasizing extensibility and SQL compliance. PostgreSQL features transaction processing, transactions ...

, as well as being adapted for others, including early versions of

Perl Perl is a high-level, general-purpose, interpreted, dynamic programming language. Though Perl is not officially an acronym, there are various backronyms in use, including "Practical Extraction and Reporting Language". Perl was developed ...

. Circa 1993, Spencer donated a second version of his RE library to

4.4BSD The history of the Berkeley Software Distribution began in the 1970s when University of California, Berkeley received a copy of Research Unix, Unix. Professors and students at the university began adding software to the operating system and releas ...

, following the

POSIX The Portable Operating System Interface (POSIX; ) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines application programming interfaces (APIs), along with comm ...

standard for regular expressions. Spencer was technical lead on the

FreeS/WAN FreeS/WAN, for Free Secure Wide-Area Networking, was a free software project which implemented a reference version of the IPsec network security layer for Linux. The project goal of ubiquitous opportunistic encryption of Internet traffic was n ...

project, implementing an IPsec

cryptographic Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or '' -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More gen ...

protocol stack The protocol stack or network stack is an implementation of a computer networking protocol suite or protocol family. Some of these terms are used interchangeably but strictly speaking, the ''suite'' is the definition of the communication protoc ...

for

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

. He also wrote 'aaa' (Amazing Awk Assembler), which is one of the longest and most complex programs ever written in the awk programming language. He also developed a 4 point font used by entomologists in labeling pinned insect specimens.

Space

Spencer is a founding member of the Canadian Space Society, and has served on its board of directors several times since 1984. He did mission analysis (planning of launch and orbits) for the CSS's Canadian Solar Sail project (now defunct), and was Software Architect for MOST, a Canadian science

microsatellite A microsatellite is a tract of repetitive DNA in which certain Sequence motif, DNA motifs (ranging in length from one to six or more base pairs) are repeated, typically 5–50 times. Microsatellites occur at thousands of locations within an organ ...

dedicated to studying variable light from stars and

extrasolar planet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first detect ...

s launched by

Eurockot Eurockot Launch Services GmbH is a commercial spacecraft launch provider and was founded in 1995. Eurockot uses an expendable launch vehicle called the Rockot to place satellites into low Earth orbit (LEO). Eurockot is jointly owned by ArianeGroup ...

in 2003. The

asteroid An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...

117329 Spencer is named in his honour. He is a highly regarded space enthusiast, and is a familiar and respected presence on several space forums on Usenet and the

Internet The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...

. From 1983 to 2007 Spencer posted over 34,000 messages to the sci.space.* newsgroups. His knowledge of space history and technology is such that the "I Corrected Henry Spencer" virtual

T-shirt A T-shirt (also spelled tee shirt, or tee for short) is a style of fabric shirt named after the T shape of its body and sleeves. Traditionally, it has short sleeves and a round neckline, known as a '' crew neck'', which lacks a collar. T-shir ...

award was created as a reward for anyone who can catch him in an error of fact.

References

External links

Brief biography of Spencer at O'Reilly Media

* Janet Wong, News@UofT, December 5, 2001
Asteroids 101
(6:33)
The Dawn Mission
(4:38)
Early Days
(6:38) �
Moon and Back
three videos of interviews at SpaceAccess 2013 conference, April 2013.
The Ten Commandments for C Programmers (Annotated Edition) by Henry Spencer
* — A paper he wrote with Geoff Collyer about software portability.
aaa - the Amazing Awk Assembler by Henry Spencer

awf - the Amazingly Workable Formatter by Henry Spencer
{{DEFAULTSORT:Spencer, Henry Living people Unix people Usenet people Free software programmers Duke University alumni 1955 births