QED is a line-oriented computer

text editor A text editor is a type of computer program that edits plain text. An example of such program is "notepad" software (e.g. Windows Notepad). Text editors are provided with operating systems and software development packages, and can be used to c ...

that was developed by Butler Lampson and

L. Peter Deutsch L Peter Deutsch (born Laurence Peter Deutsch on August 7, 1946, in Boston, Massachusetts) is an American computer scientist and composer. He is the founder of Aladdin Enterprises and creator of Ghostscript, a free software PostScript and PDF int ...

for the Berkeley Timesharing System running on the SDS 940. It was implemented by L. Peter Deutsch and Dana Angluin between 1965 and 1966. QED (for "quick editor") addressed

teleprinter A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point (telecommunications), point-to-point and point- ...

usage, but systems "for CRT displays erenot considered, since many of their design considerations erequite different."

Later implementations

Ken Thompson Kenneth Lane Thompson (born February 4, 1943) is an American pioneer of computer science. Thompson worked at Bell Labs for most of his career where he designed and implemented the original Unix operating system. He also invented the B (programmi ...

later wrote a version for CTSS; this version was notable for introducing

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. Thompson rewrote QED in

BCPL BCPL ("Basic Combined Programming Language") is a procedural, imperative, and structured programming language. Originally intended for writing compilers for other languages, BCPL is no longer in common use. However, its influence is still f ...

for

Multics Multics ("MULTiplexed Information and Computing Service") is an influential early time-sharing operating system based on the concept of a single-level memory.Dennis M. Ritchie, "The Evolution of the Unix Time-sharing System", Communications of t ...

. The Multics version was ported to the GE-600 system used at

Bell Labs Nokia Bell Labs, commonly referred to as ''Bell Labs'', is an American industrial research and development company owned by Finnish technology company Nokia. With headquarters located in Murray Hill, New Jersey, Murray Hill, New Jersey, the compa ...

in the late 1960s under

GECOS General Comprehensive Operating System (GCOS, ; originally GECOS, General Electric Comprehensive Operating Supervisor) is a family of operating systems oriented toward the 36-bit GE-600 series and Honeywell 6000 series mainframe computers. The ...

and later GCOS after

Honeywell Honeywell International Inc. is an American publicly traded, multinational conglomerate corporation headquartered in Charlotte, North Carolina. It primarily operates in four areas of business: aerospace, building automation, industrial automa ...

took over GE's computer business. The GECOS-GCOS port used I/O routines written by A. W. Winklehoff.

Dennis Ritchie Dennis MacAlistair Ritchie (September 9, 1941 – October 12, 2011) was an American computer scientist. He created the C programming language and the Unix operating system and B language with long-time colleague Ken Thompson. Ritchie and Thomp ...

and

Brian Kernighan Brian Wilson Kernighan (; born January 30, 1942) is a Canadian computer scientist. He worked at Bell Labs and contributed to the development of Unix alongside Unix creators Ken Thompson and Dennis Ritchie. Kernighan's name became widely known ...

wrote the QED manuals used at Bell Labs. Given that the authors were the primary developers of 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 ...

operating system, it is natural that QED had a strong influence on the classic

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 ...

text editors ed, sed and their descendants such as ex and sam, and more distantly AWK and

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 ...

. A version of QED named FRED (Friendly Editor) was written at the

University of Waterloo The University of Waterloo (UWaterloo, UW, or Waterloo) is a Public university, public research university located in Waterloo, Ontario, Canada. The main campus is on of land adjacent to uptown Waterloo and Waterloo Park. The university also op ...

for Honeywell systems by Peter Fraser. A University of Toronto team consisting of Tom Duff,

Rob Pike Robert Pike (born 1956) is a Canadian programmer and author. He is best known for his work on the Go programming language while working at Google and the Plan 9 operating system while working at Bell Labs, where he was a member of the Unix t ...

, Hugh Redelmeier, and David Tilbrook implemented a version of QED that runs on

; David Tilbrook later included QED as part of his QEF tool set. QED was also used as a character-oriented editor on the Norwegian-made Norsk Data systems, first Nord TSS, then Sintran III. It was implemented for the Nord-1 computer in 1971 by Bo Lewendal who after working with Deutsch and Lampson at Project Genie and at the Berkeley Computer Corporation, had taken a job with Norsk Data (and who developed the Nord TSS later in 1971).

Later implementations

See also

References

Further reading