[Appendix B] B.2 Built-in Commands and Keywords

B.2 Built-in Commands and Keywords

Here is a summary of all built-in commands and keywords.

Command	Chapter	Summary
:	7	Do nothing (just do expansions of 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.
break	5	Exit from surrounding for , select , while , or until loop.
case	5	Multi-way conditional construct.
cd	1	Change working directory.
continue		Skip to next iteration of for , select , while , or until loop.
echo	4	Expand and print arguments (obsolete).
exec	9	Replace shell with given program.
exit	5	Exit from shell.
export	3	Create environment variables.
eval	7	Process arguments as a command line.
fc	2	Fix command (edit history file).
fg	8	Put background job in foreground.
for	5	Looping construct.
function	4	Define function.
getopts	6	Process command-line options.
if	5	Conditional construct.
jobs	1	List background jobs.
kill	8	Send signal to process.
let	6	Arithmetic variable assignment.
newgrp		Start new shell with new group ID.
print	1	Expand and print arguments on standard output.
pwd	1	Print working directory.
read	7	Read a line from standard input.
readonly	6	Make variables read-only (unassignable).
return	5	Return from surrounding function or script.
select	5	Menu generation construct.
set	3	Set options.
shift	6	Shift command-line arguments.
time		Run command and print execution times.
trap	8	Set up signal-catching routine.
typeset	6	Set special characteristics of variables.
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	Looping construct.
wait	8	Wait for background job(s) to finish.
whence	3	Identify source of command.
while	5	Looping construct.