Editors at a Glance

For developers to write their programs, the first necessary tool is an editor. An editor is different from a word processor in that simple text file editors do not put any embedded formatting detail within the file, while word processors use extensive formatting details. The reason for this difference is that word processors are meant to produce documents for business and publishing and hence should embed all the necessary formatting, while text file editors should only store and process ASCII sets of characters. However, Linux/UNIX-based systems accept a LF (line feed) character to interpret text in the next line. On Windows- and MS-DOS–based systems, the next line is interpreted as the combination of CR and LF (carriage return and line feed) characters.

Computer programs and (text-based) data files are interpreted as a continuous stream of ASCII characters (and line feed characters) by the compilers and the related development tools. Therefore, we should use a text editor for creating source programs. A very ancient text editor is the vi editor, which has been used as the de-facto standard editor by most UNIX developers. The Emacs editor is the next most frequently used, particularly by programmers of recent generations. This is due to its improved user-friendly commands and interface. Any book on Linux/UNIX-based development would be incomplete without a discussion of these two editors.