Line editor

Source: Wikipedia, the free encyclopedia.

In computing, a line editor is a

home computers
, avoiding the need for a more memory-intensive full-screen editor.

Line editors are limited to typewriter keyboard text-oriented input and output methods. Most edits are a line-at-a-time. Typing, editing, and document display do not occur simultaneously. Typically, typing does not enter text directly into the document. Instead, users modify the document text by entering these commands on a text-only terminal. Commands and text, and corresponding output from the editor, will scroll up from the bottom of the screen in the order that they are entered or printed to the screen. Although the commands typically indicate the line(s) they modify, displaying the edited text within the context of larger portions of the document requires a separate command.

Line editors keep a reference to the "current line" to which the entered commands usually are applied. In contrast, modern screen based editors allow the user to interactively and directly navigate, select, and modify portions of the document. Generally line numbers or a search based context (especially when making changes within lines) are used to specify which part of the document is to be edited or displayed.

Early line editors included

IBM PC, the only editor provided in DOS was the Edlin
line editor.

Line editors are still used non-interactively in

ed commands. They are also used in many MUD
systems, though many people edit text on their own computer using MUD's download and upload features.