Editing QED (text editor) (section)

==Later implementations==
[[Ken Thompson]] later wrote a version for [[Compatible Time-Sharing System|CTSS]]; this version was notable for introducing [[regular expression]]s. Thompson rewrote QED in [[BCPL]] for [[Multics]].  The Multics version was ported to the [[GE-600 series|GE-600]] system used at [[Bell Labs]] in the late 1960s under [[General Comprehensive Operating System|GECOS]] and later GCOS after [[Honeywell]] took over [[General Electric|GE]]'s computer business.  The GECOS-GCOS port used I/O routines written by A. W. Winklehoff.  [[Dennis Ritchie]], [[Ken Thompson]] and [[Brian Kernighan]] wrote the QED manuals used at Bell Labs.<ref>D. M. Ritchie and K. L. Thompson, "QED Text Editor", [https://www.nokia.com/bell-labs/about/dennis-m-ritchie/qedman.pdf MM-70-1373-3] (June 1970), reprinted as "QED Text Editor Reference Manual", MHCC-004, Murray Hill Computing, Bell Laboratories (October 1972).</ref><ref>B. W. Kernighan, "A Tutorial Introduction to the QED Text Editor under GE-TSS", MM-70-1373-6 (June 1970), reprinted as "Tutorial Introduction to QED Text Editor", MHCC-002, Murray Hill Computing, Bell Laboratories (October, 1972).</ref><ref>B. W. Kernighan, "A Guide to the Advanced Use of QED Text Editor", MM-70-1373-7 (July 1970), reprinted as "A Guide to Advanced Use of QED Text Editor", MHCC-003, Murray Hill Computing, Bell Laboratories (October, 1972).</ref>
Given that the authors were the primary developers of the [[Unix]] operating system, it is natural that QED had a strong influence on the classic [[Unix|UNIX]] text editors [[ed (text editor)|ed]], [[sed]] and their descendants such as [[Ex (text editor)|ex]] and [[sam (text editor)|sam]],<ref>
{{citation|last=Ritchie|first=Dennis|title=An incomplete history of the QED Text Editor|location=Murray Hill|publisher=Bell Labs|date=February 12, 2004|url=https://www.bell-labs.com/usr/dmr/www/qed.html}}.</ref> and more distantly [[AWK]] and [[Perl]].

A version of QED named FRED (Friendly Editor) was written at the
[[University of Waterloo]] for Honeywell systems<ref>{{cite web|last1=Fraser|first1=Peter|title=The FRED Text Editor|url=http://www.thinkage.ca/english/gcos/product-uwtools.shtml|website=Thinkage Ltd.|access-date=1 June 2015}}</ref> by Peter Fraser.  A University of Toronto team consisting of [[Tom Duff]], [[Rob Pike]], Hugh Redelmeier, and David Tilbrook implemented a version of QED that runs on [[Unix|UNIX]]; 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).{{Citation needed|date=February 2017}}