UNIX® Shells by Example, Third Edition

B.3. bash versus sh

The Bourne Again (bash) shell has the following features not found in the traditional Bourne shell (sh).

• Formatting the prompts

• History (csh style)

• Aliases

• A built-in command line editor (emacs or vi) for editing the command line

• Directory manipulation with pushd and popd

• Csh-type job control to stop or run jobs in the background, bring them to the foreground, etc. with command such as bg, fg, Ctrl-Z, etc.

• Tilde, brace, and parameter expansion

• Key bindings to customize key sequences

• Advanced pattern matching

• Arrays

• The select loop (from Korn shell)

• Many new built-in commands

Feature	csh/tcsh	Bourne	Bash	Korn
Variables:
Assigning values to local variables	set x = 5	x=5	x=5	x=5
Assigning variable attributes			declare or typeset	typeset ...