Learning the vi and Vim Editors, 7th Edition

And These Are My Brothers, Darrell, Darrell, and Darrell

There are a number of freely available “clones” of the vi editor. Appendix D provides a pointer to a web site that lists all known vi clones, and Part II covers Vim in great detail. Part III covers an additional three of the more popular clones. They are:

• Version 1.79 of Keith Bostic’s nvi (Chapter 16)

• Version 2.2.0 of Steve Kirkendall’s elvis (Chapter 17)

• Version 9.6.4 of vile, by Kevin Buettner, Tom Dickey, Paul Fox, and Clark Morgan (Chapter 18)

All the clones were written either because the source code for vi was not freely available—making it impossible to port vi to a non-Unix environment or to study the code—or because Unix vi (or another clone!) did not provide desired functionality. For example, Unix vi often has limits on the maximum length of a line, and it cannot edit binary files. (The chapters on the various programs present more information about each one’s history.)

Each program provides a large number of extensions to Unix vi; often, several of the clones provide the same extensions, although usually not in an identical way. Instead of repeating the treatment of each common feature in each program’s chapter, we have centralized the discussion here. You can think of this chapter as presenting “what the clones do,” with each clone’s own chapter presenting “how the clone does it.”

The order in which topics are presented in this chapter is used in an expanded fashion in Part II on Vim, and in a much more compact fashion ...