Unix in a Nutshell, 4th Edition

Differing Features

The following table displays features that are different among the three shells.

bash	ksh	tcsh	Meaning/action
$	$	%	Prompt.
>|	>|	>!	Force redirection.
		>>!	Force append.
> file 2>&1	> file 2>&1	>& file	Combine stdout and stderr.
>& file		>& file	Combine stdout and stderr.
' '	' '	' '	Substitute output of enclosed command.
$()	$()		Substitute output of enclosed command. (Preferred form.)
$HOME	$HOME	$home	Home directory.
var = value	var = value	setvar=value	Variable assignment.
export var = val	export var = val	setenv var val	Set environment variable.
${ nn }	${ nn }		More than nine args can be referenced.
"$@"	"$@"		All args as separate words.
$#	$#	$#argv	Number of arguments.
$?	$?	$status	Exit status.
$!	$!		Last background Process ID.
$-	$-		Current options.
. file	. file	source file	Read commands in file.
aliasx=y	aliasx=y	alias x y	Name x stands for y.
case	case	switch/case	Choose alternatives.
cd ~-	cd ~-	popd/pushd	Switch directories.
popd/pushd		popd/pushd	Switch directories.
done	done	end	End a loop statement.
esac	esac	endsw	End case or switch.
exit [ n ]	exit [ n ]	exit [( expr )]	Exit with a status.
for/do	for/do	foreach	Loop through values.
echo -E	print -r	glob	Ignore echo escapes.
hash	alias -t	hashstat	Display ...