[shells] shells

shells

[sh] Bourne Shell – sh

(Bell Telephone Laboratories, 1979)

General shells

[ksh] KornShell – ksh

(David Korn, 1983)

[Bash] The GNU Bourne-Again Shell – Bash

(Brian Fox, 1989): Bash Reference Manual (6.4 Bash Conditional Expressions)

[zsh] Z shell – Zsh

(Paul Falstad, 1990): A User’s Guide, Documentation