Gosling Emacs (often shortened to "Gosmacs" or "gmacs") is a discontinued Emacs implementation written in 1981 by James Gosling in C. Gosling initially allowed Gosling Emacs to be redistributed with no formal restrictions, as required by the "Emacs commune" since the 1970s, but later sold it to UniPress. The disputes with UniPress inspired the creation of the first formal license for Emacs, which later became the GPL, as Congress had introduced copyright for software in 1980.

Features

Gosling Emacs was especially noteworthy because of the effective redisplay code, which used a dynamic programming technique to solve the classical string-to-string correction problem. The algorithm was quite sophisticated; that section of the source was headed by a skull-and-crossbones in ASCII art, warning any would-be improver that even if they thought they understood how the display code worked, they probably did not.

Distribution

Since Gosling had permitted its unrestricted redistribution,

Richard Stallman Richard Matthew Stallman (; born March 16, 1953), also known by his initials, rms, is an American free software movement activist and programmer. He campaigns for software to be distributed in such a manner that its users have the freedom to ...

used some Gosling Emacs code in the initial version of

GNU Emacs GNU Emacs is a free software text editor. It was created by GNU Project founder Richard Stallman, based on the Emacs editor developed for Unix operating systems. GNU Emacs has been a central component of the GNU project and a flagship project ...

. Among other things, he rewrote part of the Gosling code headed by the skull-and-crossbones comment and made it "...shorter, faster, clearer and more flexible." In 1983 UniPress began selling Gosling Emacs on

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, ...

for $395 and on VMS for $2,500, marketing it as "EMACS–multi-window text editor (Gosling version)". Controversially, Unipress asked Stallman to stop distributing his version of Emacs for Unix. UniPress never took legal action against Stallman or his nascent Free Software Foundation, believing "hobbyists and academics could never produce an Emacs that could compete" with their product. All Gosling Emacs code was removed from GNU Emacs by version 16.56 (July 1985), with the possible exception of a few particularly involved sections of the display code. The latest versions of GNU Emacs (since August 2004) do not feature the skull-and-crossbones warning.

Extension language

Its extension language, Mocklisp, has a syntax that appears similar to Lisp, but Mocklisp does not have lists or any other structured datatypes. The Mocklisp interpreter, built by Gosling and a collaborator, was replaced by a full Lisp interpreter in GNU Emacs.

References

* Christopher Kelty, "EMACS, grep, and UNIX: authorship, invention and translation in software", https://web.archive.org/web/20110728022656/http://www.burlingtontelecom.net/~ashawley/gnu/emacs/ConText-Kelty.pdf Emacs Unix text editors 1981 software {{programming-software-stub