OpenBSD KornShell (ksh) review

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

OpenBSD KornShell (ksh) is the OpenBSD Project's command interpreter for interactive sessions and shell scripts. It is aimed at people who want KornShell-style scripting alongside command-line work in an OpenBSD environment. Its language is a superset of sh, with pipelines, redirections, command lists, compound commands, functions, arrays, parameter and arithmetic expansion, and job control. Restricted-shell mode (rksh) is also available. That breadth makes it relevant to both routine terminal use and scripts that need more than basic command sequencing.

Interactive features are a meaningful part of the package rather than an afterthought: users can choose vi or Emacs command-line editing, use command and file-name completion, and configure startup behavior through ENV and .kshrc. As an OpenBSD shell, its platform fit is focused; the listed supported platform is OpenBSD. That makes it a natural fit for people working in that environment, but a less suitable choice for someone who needs one shell product across other operating systems. The language's relationship to sh may also be a consideration for teams with established shell conventions.

ksh is free and open source, distributed with OpenBSD as public-domain software. There are no paid tiers described, so buyers are choosing based on shell behavior and platform fit rather than subscription features. The listed support channel is documentation, which will suit readers comfortable consulting a manual, but may be less attractive to teams that expect other support routes. Choose ksh if OpenBSD and KornShell-style interactive and scripting features match your workflow; consider an alternative if cross-platform support or a different support model is essential.

OpenBSD KornShell (ksh) pros and cons

• Where it wins
  • Combines interactive command use with a language superset of sh.
  • Includes arrays, functions, arithmetic expansion, and job control.
  • Offers vi or Emacs editing plus command and file-name completion.
• Where it doesn't
  • Its listed supported platform is limited to OpenBSD.
  • Its command language may not suit users seeking another shell style.
  • Documentation is the listed support channel.

OpenBSD KornShell (ksh) fact sheet, pricing and score →

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Last updated 9 Oct 2026 · How we research and update