NVI

nvi, short for New Vi, is a free, open-source clone of the classic vi text editor. It was developed as a portable, maintainable reimplementation of vi and its ex command set for BSD and other Unix-like systems. The project aimed to provide a clean codebase and broad portability while preserving the editing model and basic features familiar to vi users.

Historically, nvi was distributed with several BSD variants and derivatives during the 1990s and early 2000s. As BSDs evolved, many shifted to newer vi implementations, such as Vim, but nvi remained available on some systems as a legacy or optional editor, reflecting BSD’s philosophy of providing multiple standard tools.

Implementation and features include a terminal-based, modal editing model with command mode and insert mode, plus ex-style colon commands. It relies on terminal databases (termcap/terminfo) for terminal handling and provides standard editing operations such as navigation, insertion, deletion, and basic text manipulation. While not as feature-rich as more modern successors, nvi strives for compatibility with common vi behaviors and workflows, making it usable as a drop-in editor on systems where it is installed.

Current status and relevance: nvi is largely of historical and compatibility interest. Modern users more commonly encounter Vim or other editor implementations, but nvi remains available in some BSD ports and archives as a legacy option. It serves as an example of BSD’s approach to open-source reimplementation of classic Unix tools.