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Manual Pages  — BUILTIN

NAME

builtin, amp;!, builtin%, amp;., amp;:, builtin@, amp;[, builtin{, builtin}, alias, alloc, bg, bind, bindkey, break, breaksw, builtins, case, cd, chdir, command, complete, continue, default, dirs, do, done, echo, echotc, elif, else, end, endif, endsw, esac, eval, exec, exit, export, false, fc, fg, filetest, fi, for, foreach, getopts, glob, goto, hash, hashstat, history, hup, if, jobid, jobs, kill, limit, local, log, login, logout, ls-F, nice, nohup, notify, onintr, popd, printenv, printf, pushd, pwd, read, readonly, rehash, repeat, return, sched, set, setenv, settc, setty, setvar, shift, source, stop, suspend, switch, telltc, test, then, time, times, trap, true, type, ulimit, umask, unalias, uncomplete, unhash, unlimit, unset, unsetenv, until, wait, where, which, while – shell built-in commands

CONTENTS

SYNOPSIS

See the built-in command description in the appropriate shell manual page.

DESCRIPTION

Shell builtin commands are commands that can be executed within the running shell's process. Note that, in the case of csh(1) builtin commands, the command is executed in a subshell if it occurs as any component of a pipeline except the last.

If a command specified to the shell contains a slash ‘/’, the shell will not execute a builtin command, even if the last component of the specified command matches the name of a builtin command. Thus, while specifying "echo" causes a builtin command to be executed under shells that support the echo builtin command, specifying "/bin/echo" or "./echo" does not.

While some builtin commands may exist in more than one shell, their operation may be different under each shell which supports them. Below is a table which lists shell builtin commands, the standard shells that support them and whether they exist as standalone utilities.

Only builtin commands for the csh(1) and sh(1) shells are listed here. Consult a shell's manual page for details on the operation its builtin commands. Beware that the sh(1) manual page, at least, calls some of these commands "built-in commands" and some of them "reserved words". Users of other shells may need to consult an info(1) page or other sources of documentation.

Commands marked "No**" under External do exist externally, but are implemented as scripts using a builtin command of the same name.
Command Externalcsh(1)sh(1)
amp;! amp;No amp;No Yes
% amp;No Yes amp;No
amp;. amp;No amp;No Yes
amp;: amp;No Yes Yes
@ amp;No Yes amp;No
amp;[ Yes amp;No Yes
{ amp;No amp;No Yes
} amp;No amp;No Yes
alias No** Yes Yes
alloc amp;No Yes amp;No
bg No** Yes Yes
bind amp;No amp;No Yes
bindkey amp;No Yes amp;No
break amp;No Yes Yes
breaksw amp;No Yes amp;No
builtin amp;No amp;No Yes
builtins amp;No Yes amp;No
case amp;No Yes Yes
cd No** Yes Yes
chdir amp;No Yes Yes
command No** amp;No Yes
complete amp;No Yes amp;No
continue amp;No Yes Yes
default amp;No Yes amp;No
dirs amp;No Yes amp;No
do amp;No amp;No Yes
done amp;No amp;No Yes
echo Yes Yes Yes
echotc amp;No Yes amp;No
elif amp;No amp;No Yes
else amp;No Yes Yes
end amp;No Yes amp;No
endif amp;No Yes amp;No
endsw amp;No Yes amp;No
esac amp;No amp;No Yes
eval amp;No Yes Yes
exec amp;No Yes Yes
exit amp;No Yes Yes
export amp;No amp;No Yes
false Yes amp;No Yes
fc No** amp;No Yes
fg No** Yes Yes
filetest amp;No Yes amp;No
fi amp;No amp;No Yes
for amp;No amp;No Yes
foreach amp;No Yes amp;No
getopts No** amp;No Yes
glob amp;No Yes amp;No
goto amp;No Yes amp;No
hash No** amp;No Yes
hashstat amp;No Yes amp;No
history amp;No Yes amp;No
hup amp;No Yes amp;No
if amp;No Yes Yes
jobid amp;No amp;No Yes
jobs No** Yes Yes
kill Yes Yes Yes
limit amp;No Yes amp;No
local amp;No amp;No Yes
log amp;No Yes amp;No
login Yes Yes amp;No
logout amp;No Yes amp;No
ls-F amp;No Yes amp;No
nice Yes Yes amp;No
nohup Yes Yes amp;No
notify amp;No Yes amp;No
onintr amp;No Yes amp;No
popd amp;No Yes amp;No
printenv Yes Yes amp;No
printf Yes amp;No Yes
pushd amp;No Yes amp;No
pwd Yes amp;No Yes
read No** amp;No Yes
readonly amp;No amp;No Yes
rehash amp;No Yes amp;No
repeat amp;No Yes amp;No
return amp;No amp;No Yes
sched amp;No Yes amp;No
set amp;No Yes Yes
setenv amp;No Yes amp;No
settc amp;No Yes amp;No
setty amp;No Yes amp;No
setvar amp;No amp;No Yes
shift amp;No Yes Yes
source amp;No Yes amp;No
stop amp;No Yes amp;No
suspend amp;No Yes amp;No
switch amp;No Yes amp;No
telltc amp;No Yes amp;No
test Yes amp;No Yes
then amp;No amp;No Yes
time Yes Yes amp;No
times amp;No amp;No Yes
trap amp;No amp;No Yes
true Yes amp;No Yes
type No** amp;No Yes
ulimit No** amp;No Yes
umask No** Yes Yes
unalias No** Yes Yes
uncomplete amp;No Yes amp;No
unhash amp;No Yes amp;No
unlimit amp;No Yes amp;No
unset amp;No Yes Yes
unsetenv amp;No Yes amp;No
until amp;No amp;No Yes
wait No** Yes Yes
where amp;No Yes amp;No
which Yes Yes amp;No
while amp;No Yes Yes

SEE ALSO

csh(1), echo(1), false(1), info(1), kill(1), login(1), nice(1), nohup(1), printenv(1), printf(1), pwd(1), sh(1), test(1), time(1), true(1), which(1)

HISTORY

The builtin manual page first appeared in FreeBSD 3.4 .

AUTHORS

This manual page was written by Sheldon Hearn <Mt sheldonh@FreeBSD.org>.

BUILTIN (1) December 21, 2010

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