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About vi The name vi is an initialism (pronounced not ) and comes from the shortest unambiguous abbreviation for the command visual in '''ex'''. The command in question switches the line editor '''ex''' to visual mode. Typically, as a matter of convenience, the same program will start up in vi or ex mode, depending on the name with which it is started. vi is a modal editor and assigns different meanings to buttons or keystrokes depending on the active editing mode. In insert mode, text typed is inserted into the document. Pressing the escape key while in insert mode will switch the editor to command mode, where letters correspond to cursor movements or editing functions. For example: "j" to move the cursor down a line, "k" to move up a line, "x" to delete the character at the current cursor position, and "i" to return to insert mode. (Arrow keys also work, provided that vi knows the user's terminal type.) Keys pressed while in command mode are not inserted into the text, which is a common cause for confusion among new users. In command mode, multiple editing operations can be performed in a row with simple keystrokes, without having to hold down the Early versions of vi did not give any indication as to which mode they were in, and it is typical of users to simply press the Escape key to ensure that the editor is in command mode (it will beep if already in command mode). Current versions of vi indicate the mode on the status line or graphically. Newer versions of vi also permit use of the PgUp, PgDn, Home, End and Del keys, provided that the terminal type has been correctly set (using the TERM environment variable). Graphical implementations of vi (for example, gvim) also fully support the use of a mouse and menus to access editing commands. vi became the de facto standard Unix editor and a nearly undisputed hacker favorite outside of MIT until the rise of Emacs after about 1984. As of 2006 either vi or one of its clones can still be found on nearly all installations of Unix. The Single UNIX Specification specifies vi, so any system conforming to the Single UNIX Specification will have vi. vi is still widely used by users of Unix variants. About half the respondents in a 1991 USENET poll preferred vi. It starts up faster than the bulkier versions of Emacs and uses less memory. Consequently, even some Emacs fans will resort to it as a mail editor and for small editing jobs. In 1999, Tim O'Reilly, founder of the eponymous computer book publisher, stated that his company sold more copies of its vi book than its emacs book *. When a "rescue floppy" is being built for restores following a hard drive crash, vi is often the editor chosen because it is compact enough to fit on a floppy, and because almost anyone performing rescue operations will be able to use it. vi and Emacs are classically the two sides in the editor wars. vi trivia vi derivatives and clones See also Further reading Oualline, Steve (2001) Vi IMproved - Vim, New Riders Publishers, 572 pp. | ||||||||||
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