Built-In Commands and Reserved Words

B.2 Built-In Commands and Reserved Words

Table 2.3 shows a summary of all built-in commands and reserved words.

Table B.3. Commands and Reserved Words
Command	Chapter	Summary
!	5	Reserved word. Logical NOT of a command exit status.
:	7	Do nothing (just do expansions of any arguments).
.	4	Read file and execute its contents in current shell.
alias	3	Set up shorthand for command or command line.
bg	8	Put job in background.
bind	2	Bind a key sequence to a readline function or macro.
break	5	Exit from surrounding for , select , while , or until loop.
builtin	5	Execute the specified shell built-in.
case	5	Reserved word. Multi-way conditional construct.
cd	1	Change working directory.
command	7	Run a command bypassing shell function lookup.
continue		Skip to next iteration of for , select , while , or until loop.
declare	6	Declare variables and give them attributes.
dirs	6	Display the list of currently remembered directories.
disown	8	Remove a job from the job table.
do	5	Reserved word. Part of a for , select , while , or until looping construct.
done	5	Reserved word. Part of a for , select , while , or until looping construct.
echo	4	Expand and print any arguments.
elif	5	Reserved word. Part of an if construct.
else	5	Reserved word. Part of an if construct.
enable	7	Enable and disable built-in shell commands.
esac	5	Reserved word. Part of a case construct.
eval	7	Run the given arguments through command-line processing.
exec	9	Replace the shell with the given program.
exit	5	Exit from the shell.
export	3	Create environment variables.
fc	2	Fix command (edit history file).
fg	8	Put background job in foreground.
fi	5	Reserved word. Part of an if construct.
for	5	Reserved word. Looping construct.
function	4	Define a function.
getopts	6	Process command-line options.
hash	3	Full pathnames are determined and remembered.
help	1	Display helpful information on built-in commands.
history	1	Display command history.
if	5	Reserved word. Conditional construct.
in	5	Reserved word. Part of a case construct.
jobs	1	List any background jobs.
kill	8	Send a signal to a process.
let	6	Arithmetic variable assignment.
local	4	Create a local variable.
logout	1	Exits a login shell.
popd	4	Removes a directory from the directory stack.
pushd	4	Adds a directory to the directory stack.
pwd	1	Print the working directory.
read	7	Read a line from standard input.
readonly	6	Make variables read-only (unassignable).
return	5	Return from the surrounding function or script.
select	5	Reserved word. Menu-generation construct.
set	3	Set options.
shift	6	Shift command-line arguments.
suspend		Suspend execution of a shell.
test	5	Evaluates a conditional expression.
then	5	Reserved word. Part of an if construct.
time		Reserved word. Run command pipeline and print execution times. The format of the output can be controlled with TIMEFORMAT .
times		Print the accumulated user and system times for processes run from the shell.
trap	8	Set up a signal-catching routine.
type	3	Identify the source of a command.
typeset	6	Declare variables and give them attributes. Same as declare .
ulimit	10	Set/show process resource limits.
umask	10	Set/show file permission mask.
unalias	3	Remove alias definitions.
unset	3	Remove definitions of variables or functions.
until	5	Reserved word. Looping construct.
wait	8	Wait for background job(s) to finish.
while	5	Reserved word. Looping construct.