BASH(1) General Commands Manual BASH(1) bash - - (Bourne-Again SHell) bash [] [_ | ] Bash is Copyright (C) 1989-2025 by the Free Software Foundation, Inc. Bash . (Bourne shell) . Bash Korn C (ksh csh). POSIX . Bash IEEE POSIX ( IEEE 1003.1). Bash POSIX ( posix mode) . posix bash. Bash POSIX . set -o . bash : -c -c command_string. command_string $0 . $0 . -i -i . -l bash ( ). -r -r ( ). -s -s . . -D $ . C POSIX. -n . [-+]O [shopt_option] shopt_option shopt ( ). shopt_option -O +O. shopt_option bash shopt . +O . -- -- . -- ( ) . - --. Bash . . --debugger . ( extdebug shopt ). --dump-po-strings -D GNU gettext "po" ( - portable object). --dump-strings -D. --help . --init-file file --rcfile file ~/.bashrc ( INVOCATION ). --login -l. --noediting GNU readline . --noprofile ~/.bash_profile ~/.bash_login ~/.profile. bash ( ). --norc ~/.bashrc . sh. --posix posix bash POSIX . --restricted ( ). --verbose -v. --version bash . -c -s ( ). bash $0 . bash . bash . 0. bash PATH . - --login. ( -s) -c ( isatty(3)) -i. bash PS1 i $- . bash . bash . (Tildes) . bash --login /etc/profile . ~/.bash_profile ~/.bash_login ~/.profile . --noprofile . exit bash ~/.bash_logout . bash ~/.bashrc . --norc . --rcfile file bash file ~/.bashrc bash BASH_ENV . bash : if [ -n "$BASH_ENV" ]; then . "$BASH_ENV"; fi PATH . bash sh sh POSIX . --login /etc/profile ~/.profile . --noprofile . sh bash ENV . sh --rcfile . sh . sh bash posix . bash posix --posix POSIX . ENV . . bash rshd sshd. bash ~/.bashrc . bash sh. --norc --rcfile bash ~/.bashrc rshd sshd . ( ) ( ) -p SHELLOPTS BASHOPTS CDPATH GLOBIGNORE . -p . . (blank) (tab). (whitespace) space isspace(3) . (word) . (token). name . (identifier). (metacharacter) . : | & ; ( ) < > space tab newline (control operator) (token) . : || & && ; ;; ;& ;;& ( ) | |& . ( ) case select ( in ) for ( in do ): ! case coproc do done elif else esac fi for function if in select then until while { } time [[ ]] . . . . 128+n n. (Pipelines) | |&. : [time [-p]] [ ! ] command1 [ [|||&] command2 ... ] command1 command2. command1 ( ). |& command1 command2 2>&1 |. command1. pipefail. pipefail ( ) . ! . . time . -p POSIX (token) "-". TIMEFORMAT TIMEFORMAT . posix time . . TIMEFORMAT . . . lastpipe shopt ( shopt ) . ; & && || ; & <_>. && || ; & . . & . 0. . ; . . AND OR && || . AND OR . AND command1 && command2 command2 command1 (). OR command1 || command2 command2 command1 . AND OR . . . (list) ( ). . . { list; } . . . . ( ) { } . . ((expression)) . 0 1. . 0. [[ expression ]] () (). . [[ ]] . . -f . [[ < > . == != extglob . = ==. nocasematch . 0 (==) (!=) 1 . : . =~ == !=. POSIX ( POSIX regcomp regexec regex(3)). 0 1 . 2. nocasematch . . . . . ^ $ . BASH_REMATCH . 0 BASH_REMATCH . BASH_REMATCH . n BASH_REMATCH n. Bash BASH_REMATCH . : ( expression ) . . ! expression . expression1 && expression2 expression1 expression2 . expression1 || expression2 expression1 expression2 . && || expression2 expression1 . for name [ [ in word ... ] ; ] do list ; done in . name . in word for ( ). . in 0. for (( expr1 ; expr2 ; expr3 )) [;] do list ; done expr1 . expr2 . expr2 expr3. 1. . break continue ( ) . select name [ in word ] ; do list ; done in . in word ( ). select PS3 . select name . select . (EOF) select 1. name . REPLY. break. select . case word in [ [(] pattern [ | pattern ] ... ) list ;; ] ... esac case word pattern . ) . word . pattern . nocasematch . (clause) . case . ;; case case . ;& ;; . ;;& ;; case . . . if list; then list; [ elif list; then list; ] ... [ else list; ] fi if list. then list. elif list then list . else list . . while list-1; do list-2; done until list-1; do list-2; done while list-2 list-1 . until while : list-2 list-1 . while until list-2 . (Coprocesses) coproc. & . : coproc [] [_] . ( ). . COPROC. coproc { [_]; } COPROC . . coproc : . . ( ) . [0]. [1]. ( _ ). . . _PID. wait . coproc . . . : _ () - [-] function _ [()] - [-] _. function . function . - ( ). { } . function . - _ . posix _ POSIX $. ( _ ) . . . ( .) interactive_comments shopt ( ) # . . . interactive_comments . interactive_comments . . . . ( ) ! . : . (\) . < >. \< > \< > ( ). . . $ ` \ !. posix ! . $ ` . : $ ` " \ < >. . . ! . !. * @ ( ). $'' . ANSI C. : \a () \b backspace \e \E \f \n \r \t \v \\ backslash \' \" \? \nnn nnn ( ). \xHH HH ( ). \uHHHH (ISO/IEC 10646) HHHH ( ). \UHHHHHHHH (ISO/IEC 10646) HHHHHHHH ( ). \cx -x. . ($"") . gettext LC_MESSAGES TEXTDOMAINDIR TEXTDOMAIN. C POSIX . . noexpand_translation shopt . shopt . . . . . declare ( declare ). export readonly . . . unset ( ). =[] . (tilde) ( ). integer $((...)) ( ). . alias declare typeset export readonly local ( ). posix command . "+=" . declare . "+=" integer . . "+=" ( ) ( "="), ( ) - . . nameref -n declare local ( declare local ) . . ( nameref ) . . declare -n ref=$1 ref . ref $1. for . nameref. . -n unset. unset . ( ). 0. set. . ( ). ( ). $ ($1-$9) $0 ( ). . . . * ($*) . . . IFS. "$*" "$1c$2c..." c IFS. IFS . IFS . @ ($@) . . . . "$@" "$1" "$2" ... . "$@" $@ ( ). # ($#) . ? ($?) . - ($-) set ( -i). $ ($$) . . ! ($!) bg ( ). 0 ($0) . . bash $0 . bash -c $0 . bash . : _ ($_ ) . _ . . . $_ . BASH bash . BASHOPTS . -s shopt ( ). BASHOPTS shopt . bash . . . BASHPID bash . $$ bash. BASHPID. BASHPID . BASH_ALIASES alias. . BASH_ALIASES . BASH_ARGC bash . ( . source) . BASH_ARGC. BASH_ARGC ( extdebug shopt ). extdebug extdebug . BASH_ARGC . BASH_ARGV bash . . BASH_ARGV. BASH_ARGV ( extdebug shopt ). extdebug extdebug . BASH_ARGV . BASH_ARGV0 ( $0 0 ). BASH_ARGV0 $0 . BASH_ARGV0 . BASH_CMDS (hash) hash. . BASH_CMDS . BASH_COMMAND (trap) . BASH_COMMAND . BASH_EXECUTION_STRING -c. BASH_LINENO FUNCNAME. ${BASH_LINENO[$i]} (${BASH_SOURCE[$i+1]}) ${FUNCNAME[$i]} ( ${BASH_LINENO[$i-1]} ). LINENO . BASH_LINENO . BASH_LOADABLES_PATH enable . BASH_MONOSECONDS (monotonic clock) . EPOCHSECONDS. BASH_MONOSECONDS . BASH_REMATCH =~ [[. 0 . n n. BASH_SOURCE FUNCNAME. ${FUNCNAME[$i]} ${BASH_SOURCE[$i]} ${BASH_SOURCE[$i+1]}. BASH_SOURCE . BASH_SUBSHELL . 0. BASH_SUBSHELL . BASH_TRAPSIG (trap) . trap . BASH_VERSINFO bash . : BASH_VERSINFO[0] (release). BASH_VERSINFO[1] (version). BASH_VERSINFO[2] (patch level). BASH_VERSINFO[3] . BASH_VERSINFO[4] ( beta). BASH_VERSINFO[5] MACHTYPE. BASH_VERSION bash ( 5.2.37(3)-release). COMP_CWORD ${COMP_WORDS} . ( ). COMP_KEY ( ) . ( ). COMP_LINE . ( ). COMP_POINT . ${#COMP_LINE}. ( ). COMP_TYPE : TAB ? ! @ % . ( ). COMP_WORDBREAKS readline . COMP_WORDBREAKS . COMP_WORDS ( ) . readline COMP_WORDBREAKS . ( ). COPROC ( ) ( ). DIRSTACK ( ) . dirs. pushd popd . . DIRSTACK . EPOCHREALTIME ( time(3)) . EPOCHREALTIME. EPOCHREALTIME . EPOCHSECONDS ( time(3)). EPOCHSECONDS. EPOCHSECONDS . EUID . . FUNCNAME . 0 . ( ) "main". . FUNCNAME. FUNCNAME . BASH_LINENO BASH_SOURCE. FUNCNAME BASH_LINENO BASH_SOURCE . ${FUNCNAME[$i]} ${BASH_SOURCE[$i+1]} ${BASH_LINENO[$i]}. caller . GROUPS . GROUPS. GROUPS . HISTCMD . HISTCMD. HISTCMD . HOSTNAME . HOSTTYPE bash. . LINENO ( 1) . . LINENO . MACHTYPE bash cpu-company-system GNU. . MAPFILE ( Arrays ) mapfile . OLDPWD cd. OPTARG getopts ( ). OPTIND getopts ( ). OSTYPE bash. . PIPESTATUS ( Arrays ) ( ). bash PIPESTATUS ( [[ (( . PPID (PID) . . PWD cd. RANDOM 0 32767. RANDOM () . . RANDOM . READLINE_ARGUMENT readline "bind -x" ( ) . READLINE_LINE readline "bind -x" ( ). READLINE_MARK ( ) readline "bind -x" ( ). . READLINE_POINT readline "bind -x" ( ). REPLY read . SECONDS . SECONDS . . SECONDS . SHELLOPTS . -o set ( ). SHELLOPTS on () set -o. bash . . . SHLVL bash. SRANDOM 32 . /dev/urandom arc4random(3) . . SRANDOM . UID (user ID) . . . bash . BASH_COMPAT . . ( 4.2) ( 42) . BASH_COMPAT . BASH_COMPAT . . 4.2 42 shopt compat42 42. . BASH_ENV bash . BASH_ENV . PATH . BASH_XTRACEFD bash "set -x" . BASH_XTRACEFD . BASH_XTRACEFD . BASH_XTRACEFD 2 ( ) . CDPATH cd. cd. ".:~:/usr". CHILD_MAX . Bash POSIX ( 8192) . . COLUMNS select . checkwinsize SIGWINCH. COMPREPLY bash ( ). . EMACS bash "t", Emacs . ENV BASH_ENV ( ) posix. EXECIGNORE ( ) PATH. PATH. [ test [[. EXECIGNORE. . extglob. FCEDIT fc. FIGNORE ( READLINE ). FIGNORE . ".o:~". FUNCNEST 0 . . GLOBIGNORE . GLOBIGNORE . extglob. GLOBSORT . . LC_COLLATE. + () - . name numeric size mtime atime ctime blocks inode . ( ) . -mtime ( ). numeric ( "2" "10", ). numeric . nosort bash - . name + - . . HISTCONTROL . ignorespace (space) . ignoredups . ignoreboth ignorespace ignoredups. erasedups . . HISTCONTROL bash HISTIGNORE. HISTCONTROL. . HISTFILE ( HISTORY ). bash ~/.bash_history HISTFILE . HISTFILESIZE . . . history . 0 . . HISTSIZE . HISTIGNORE . HISTIGNORE . ( bash "*"). HISTCONTROL. "&" . "&"; . HISTIGNORE. . extglob. HISTIGNORE HISTCONTROL. "&" "ignoredups", "[ ]*" "ignorespace". "ignoreboth". HISTSIZE ( ). 0 . ( ). 500 . HISTTIMEFORMAT strftime(3) history . . . HOME cd. (tilde). HOSTFILE /etc/hosts . bash . HOSTFILE bash /etc/hosts . HOSTFILE bash . IFS read . . "". IGNOREEOF EOF . EOF bash. 10. EOF . INPUTRC readline ~/.inputrc ( READLINE ). INSIDE_EMACS bash Emacs TERM. LANG LC_. LC_ALL LANG LC_ . LC_COLLATE . LC_CTYPE . LC_MESSAGES $. LC_NUMERIC . LC_TIME . LINES select . checkwinsize SIGWINCH. MAIL MAILPATH bash Maildir. MAILCHECK () bash . 60 . . . MAILPATH . "?". $_ . : MAILPATH='/var/mail/bfox?" ":~/shell-mail?"$_ !"' Bash ( ) ( /var/mail/$USER). OPTERR 1 bash getopts ( ). OPTERR 1 . PATH . ( ). (null) PATH . . bash. /usr/local/bin:/usr/local/sbin:.if 0<78n .br /usr/bin:/usr/sbin:/bin:/sbin POSIXLY_CORRECT bash posix --posix . bash posix "set -o posix" . posix . PROMPT_COMMAND . . PROMPT_DIRTRIM \w \W ( PROMPTING ). . PS0 ( PROMPTING ) . PS1 ( PROMPTING ) . "\s-\v\$ ". PS2 PS1 . "> ". PS3 select ( SHELL GRAMMAR ). PS4 PS1 bash . PS4 . "+ ". SHELL . bash . TIMEFORMAT time. % . . %% % . %[p][l]R . %[p][l]U . %[p][l]S . %P (%U + %S) / %R. p . 0 . time p 6 6. p time . l MMmSS.FFs. p . bash $'\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS'. bash . . TMOUT read . select TMOUT . . Bash . TMPDIR bash bash . auto_resume . . . jobs. exact substring . substring %? ( JOB CONTROL ). ( prefix) %string. histchars ( HISTORY EXPANSION ). "!". "^". . "#", . . . Bash . declare . . ( ARITHMETIC EVALUATION ) . . . 0. . . Bash name[subscript]=value . subscript () . declare -a name ( ). declare -a name[subscript] subscript. declare -A name . declare readonly. . name=(value1 ... valuen) value [subscript]=string. string. value EXPANSION values . . . : name=( key1 value1 key2 value2 ...). name=( [key1]=value1 [key2]=value2 ...). . / . declare. name[subscript]=value . name name -1 . "+=" PARAMETERS . ${name[subscript]}. . subscript @ * name . . ${name[*]} IFS ${name[@]} name . ${name[@]} . . * @ ( Special Parameters ). ${#name[subscript]} ${name[subscript]}. subscript * @ . subscript -1 . 0. bash . . . () . ${!name[@]} ${!name[*]} name. @ * . unset . unset name[subscript] subscript . . . unset name name . unset name[subscript] name subscript * @. name * @. name unset . unset ( unset a[4]) . ( unset 'a[4]'). declare local readonly -a -A . -A. read -a . set declare . ( mapfile) . . . : . : ( ) . : . . . . . "$@" "${name[@]}" $* ${name[*]} ( PARAMETERS). . . . . . . a{d,c,b}e "ade ace abe". x..y[..incr] x y incr . x y . x y . x y C. x y ( ). . 1 -1 . . . Bash . . . A "{" Q , . "${" "}". : mkdir /usr/local/src/bash/{old,new,dist,bugs} chown root /usr/{ucb/{ex,edit},lib/{ex?.?*,how_ex}} sh. sh . Bash . sh "file{1,2}" . Bash "file1 file2" . bash +B +B set ( SHELL BUILTIN COMMANDS ) sh. ( "~"), ( ) . . HOME. HOME . . "~+", PWD . "~-", OLDPWD . N "+" "-", dirs . "+" "-", "+". . . Bash : = . PATH MAILPATH CDPATH . Bash ( PARAMETERS) . Bash posix. "$" . . "}" . ${parameter} parameter. parameter parameter . parameter (PARAMETERS) (Arrays). parameter (!) parameter nameref . Bash parameter parameter parameter . . . parameter parameter . ${!prefix*} ${!name[@]} . . word . ( :-) bash . . ${parameter:-word} . parameter word. parameter. ${parameter:=word} . parameter word parameter parameter. . ${parameter:?word} . parameter word ( word ) . . parameter. ${parameter:+word} . parameter word. parameter. ${parameter:offset} ${parameter:offset:length} . length parameter offset. parameter @ * @ * . :length ( ) parameter offset . offset 0. length offset 0. length offset ( ARITHMETIC EVALUATION ). offset parameter. length parameter offset . :-. parameter @ * length offset. offset -1 ( 0 ). length . parameter @ * length ${parameter[offset]}. offset . length . . 1 . offset 0 $0. ${!prefix*} ${!prefix@} . prefix IFS . @ . ${!name[@]} ${!name[*]} . name () name. name 0 name . @ . ${#parameter} . parameter. parameter * @ . parameter * @ . parameter parameter -1 . ${parameter#word} ${parameter##word} . word parameter Pattern Matching . parameter parameter ( "#" ) ( "##" ). parameter @ * . parameter @ * . ${parameter%word} ${parameter%%word} . word parameter Pattern Matching . parameter parameter ( "%" ) ( "%%" ). parameter @ * . parameter @ * . ${parameter/pattern/string} ${parameter//pattern/string} ${parameter/#pattern/string} ${parameter/%pattern/string} . pattern parameter Pattern Matching . pattern string. string . . parameter pattern ( ) pattern string. pattern # ( ) parameter. pattern % ( ) parameter. string pattern / pattern. patsub_replacement shopt & string pattern. string . & string & . \\ . string . & string & & . . nocasematch . parameter @ * . parameter @ * . ${parameter^pattern} ${parameter^^pattern} ${parameter,pattern} ${parameter,,pattern} . parameter. pattern . Bash parameter pattern . . . "^" pattern "," . ^ , pattern ^^ ,, pattern. pattern ? . parameter @ * . parameter @ * . ${parameter@operator} . parameter parameter operator. operator : U parameter . u parameter . L parameter . Q parameter . E parameter $'...'. P parameter ( ). A declare parameter . K ( ) parameter - ( ). . a parameter. k K . parameter @ * . parameter @ * . . . : $(command) () `command`. Bash command . . $(cat file) $(< file). $ ` \. . $(command) . : ${c command;} command . c | ( ). Bash . command ( exit ). : return command . | REPLY command command . Bash REPLY command REPLY command . . . bash . . : $((expression)) expression expression . . . Bash 0. . . expression bash . . <(list) >(list). list . . >(list) list. <(list) list. < > . (FIFOs) /dev/fd . . . . IFS . IFS ( ) IFS. IFS space . IFS <><><_> IFS . IFS (null) null ( ) . IFS . IFS IFS IFS IFS . IFS IFS IFS IFS . IFS . IFS . (null) ("" '') . . . . "-d''" "-d" . -f bash * ? [. ( ) GLOBSORT. nullglob . nullglob . failglob bash . nocaseglob . "." dotglob. . .. "." ( ".?"), dotglob. globskipdots . .. ".". "." . . shopt nocaseglob nullglob globskipdots failglob dotglob. GLOBIGNORE pattern. GLOBIGNORE GLOBIGNORE . nocaseglob GLOBIGNORE . . .. GLOBIGNORE . GLOBIGNORE dotglob "." . ".", ".*" GLOBIGNORE. dotglob GLOBIGNORE . GLOBIGNORE extglob. GLOBSORT . . NUL . . . : * . globstar * * . / * . ? . [...] . . . [ ! ^ . - . ] . LC_COLLATE LC_ALL . [a-d] [abcd] LC_COLLATE LC_ALL C globasciiranges. [:class:] class POSIX : alnum alpha ascii blank cntrl digit graph lower print punct space upper word xdigit . word _. [=c=] ( ) c. [.symbol.] symbol. extglob shopt . pattern-list |. : ?(pattern-list) . *(pattern-list) . +(pattern-list) . @(pattern-list) . !(pattern-list) . extglob . extglob . dotglob : dotglob ".", . .. "." ".". globskipdots . .. . "." . . . \ ' " . . . exec . . . {varname}. >&- <&- 10 varname. {varname} >&- <&- varname . {varname} exec. varredir_close . "<", ( 0). ">", ( 1). word . bash . . ls > dirlist 2>&1 dirlist ls 2>&1 > dirlist dirlist dirlist. Bash . bash bash . /dev/fd/fd fd fd. /dev/stdin 0. /dev/stdout 1. /dev/stderr 2. /dev/tcp/host/port host port bash TCP . /dev/udp/host/port host port bash UDP . . 9 . word n ( 0) n. : [n] word n ( 1) n. . : [n]>word > noclobber set word . >| > noclobber set bash word . word n ( 1) n. . : [n]>>word ( 1) ( 2) word. : &>word >&word . >word 2>&1 word -. ( Duplicating File Descriptors ) . ( 1) ( 2) word. : &>>word >>word 2>&1 ( Duplicating File Descriptors ). "" (Here Documents) delimiter ( ). ( n n) . "" : [n]<<[-]word here-document delimiter word. word delimiter word "". word delimiter word "" : "" \ \ \ $ ` . <<- delimiter. "" . \ : . "" . "" (Here Strings) "" : [n]<< word (~) . . ( n n). [n]<&word . word n . word . word - n. n ( 0). [n]>&word . n ( 1). word . word - n. n word - . [n]<&digit- digit n ( 0) n. digit n. [n]>&digit- digit n ( 1) n. [n]<>word word n 0 n. . . alias unalias ( SHELL BUILTIN COMMANDS ). . . . / $ ` = (metacharacters) . . . ls ls -F bash . . alias unalias. . ( FUNCTIONS ) . expand_aliases shopt ( shopt SHELL BUILTIN COMMANDS ). . Bash . . . . . . . alias . . SHELL GRAMMAR . . ( ). . # . 0 . FUNCNAME . : (traps) DEBUG RETURN ( trap SHELL BUILTIN COMMANDS ) trace ( declare ) -o functrace set ( DEBUG RETURN) ERR -o errtrace. local (local variables). . local ( ). . "global" . local declare . "shadow" . : . . . . . . var func1 func1 func2 var func2 var func1 var. unset : unset . ( ) . . unset ( localvar_unset ). FUNCNEST 0 . . return . return return. RETURN . # . -f declare typeset . -F declare typeset ( extdebug ). ( ) -f export. -f unset . (recursive). FUNCNEST . bash . ( let declare (( for [[ Arithmetic Expansion). 0 . C. . . id++ id-- ++id --id - + ! ~ ** * / % + - << >> <= >= < > == != & AND ^ OR (XOR) | OR && AND || OR expr?expr:expr = *= /= %= += -= <<= >>= &= ^= |= expr1 , expr2 . . "x" x . 0 . (integer) declare -i. 0. . C . 0 . 0x 0X . [base#]n base 2 64 n . base# 10. n 9 @ _ . base 36 10 35. . . [[ test [ . test [ . . . . bash . bash bash : file /dev/fd/n bash n. file /dev/stdin /dev/stdout /dev/stderr bash 0 1 2 . . [[ posix < > . posix test ASCII. -a file file . -b file file . -c file file . -d file file . -e file file . -f file file . -g file file set-group-id . -h file file . -k file file "sticky" . -p file file (FIFO). -r file file . -s file file . -t fd fd . -u file file set-user-id . -w file file . -x file file . -G file file (effective group id). -L file file . -N file file . -O file file (effective user id). -S . -o _ _ . -o set . -v _ _ ( ). _ @ * . _ @ * . -R _ _ . -z . -n . 1 = 2 string1 = string2 . = test POSIX ( ). 1 != 2 . 1 < 2 1 2 . 1 > 2 1 2 . 1 -ef 2 1 2 (inode). 1 -nt 2 1 ( ) 2 1 2 . 1 -ot 2 1 2 2 1 . 1 OP 2 OP -eq -ne -lt -le -gt -ge. 1 2 . 1 2 . [[ 1 2 ( ). [[ 1 2 0. . 1. ( ) . 2. . . 3. REDIRECTION. 4. = (tilde) . . ( ) . . . . . . . . . . . FUNCTIONS. . . bash PATH . bash (hash table) ( hash SHELL BUILTIN COMMANDS ). Bash PATH . command_not_found_handle. . 127. . 0 . . Bash . ( hash SHELL BUILTIN COMMANDS) . #! . . . : o exec. o cd pushd popd . o umask . o (traps) trap. o set . o . o ( ) set. o shopt. o alias. o $$ PPID. . . o . o . o . o . o . . subshell . . (pipeline) lastpipe . . posix -e . posix bash -e . inherit_errexit posix. & /dev/null. . . - =. . . . export declare -x unset . . unset export -n export declare -x. PARAMETERS . . . -k ( set ) . bash _ . waitpid . 0 255 125 . . . . . N bash 128+N . 127. 126. . 0 () () . 2 . $?. bash . exit . bash SIGTERM ( kill 0 ) SIGINT ( wait ). bash SIGINT . bash SIGQUIT. bash SIGTTIN SIGTTOU SIGTSTP. trap . bash trap . SIGINT SIGQUIT . SIGTTIN SIGTTOU SIGTSTP. SIGHUP. SIGHUP . SIGCONT SIGHUP ( JOB CONTROL ). disown ( SHELL BUILTIN COMMANDS ) SIGHUP disown -h. huponexit shopt bash SIGHUP . bash . bash wait wait 128 . bash SIGINT ( ^C) . ^C SIGINT . bash . bash . bash . JOB CONTROL . bash SIGINT SIGINT: 1. SIGINT bash SIGINT SIGINT ( SIGINT ). 2. SIGINT SIGINT . bash SIGINT SIGINT ( emacs ) . bash SIGINT . bash SIGINT . SIGINT . SIGINT bash SIGINT ( 1 ) . () () . bash. (pipeline). jobs. jobs . 1. bash ( ) : [1] 25647 1 25647. . Bash . . . . ( ) SIGINT. . . "stty tostop", . SIGTTIN (SIGTTOU) ( "tostop" ) . bash bash . ( ^Z Control-Z) bash. ( ^Y Control-Y) bash. bg fg kill . . SIGSTOP kill. . % (jobspec). n %n. . %ce ce. %?ce ce. bash . %% %+ . % ( ) . %- . . . . %+ %- . ( jobs) + -. : %1 "fg %1", 1 . "%1 &" 1 "bg %1". . bash . -b set bash . Bash SIGCHLD . bash bash . jobs wait . 1. bash ( checkjobs shopt) checkjobs . jobs . bash . wait wait . -f wait . bash PS1 PS2 . Bash PROMPT_COMMAND . PROMPT_COMMAND Bash . Bash PS0 . Bash PS4 -x . Bash PS0 PS1 PS2 PS4 : \a ASCII (07). \d "Weekday Month Date" ( "Tue May 26"). \D{} strftime(3) . . \e ASCII (033). \h ".". \H . \j . \l ( "ttys0"). \n . \r . \s : $0 ( ). \t 24 HH:MM:SS. \T 12 HH:MM:SS. \@ 12 /. \A 24 HH:MM. \u . \v bash ( 2.00). \V bash + ( 2.00.0) \w PWD ( $PWD) $HOME ( PROMPT_DIRTRIM). \W $PWD $HOME . \! . \# . \$ (UID) 0 # $. \nnn nnn. \\ . \[ . \] . : ( HISTORY ) . promptvars ( shopt SHELL BUILTIN COMMANDS ). . READLINE --noediting . -e read . emacs vi. -o emacs -o vi set ( SHELL BUILTIN COMMANDS ). +o emacs +o vi set. Readline Emacs . C-key C-n Control-N. meta M-key M-x Meta-X. Meta "Alt" "Option". Meta M-x ESC x Escape x . ESC meta. M-C-x ESC Control-x: Escape Control x . Meta (0200). enable-meta-key . meta ESC . Meta ESC meta M-key ( Readline Key Bindings ) force-meta-prefix. Readline . . ( kill-line) . . . . Readline : readline active-region-start-color. enable-active-region . . (). . . . Readline Readline ( inputrc). INPUTRC. ~/.inputrc. readline /etc/inputrc. readline readline . inputrc. . # . $ . . inputrc. readline bash . M-Control-u: universal-argument C-Meta-u: universal-argument inputrc M-C-u readline universal-argument. : DEL ESC ESCAPE LFD NEWLINE RET RETURN RUBOUT ( ) SPACE SPC TAB. readline (macro). . Readline inputrc . . : Meta- Control- . . . keyname:function-name macro keyname . : Control-u: universal-argument Meta-Rubout: backward-kill-word Control-o: "> output" C-u universal-argument M-DEL backward-kill-word C-o ( "> output" ). "keyseq":function-name macro keyseq keyname . GNU Emacs . "\C-u": universal-argument "\C-x\C-r": re-read-init-file "\e[11~": "Function Key 1" C-u universal-argument. C-x C-r re-read-init-file ESC [ 1 1 ~ "Function Key 1". GNU Emacs \C- . \M- meta meta force-meta-prefix. \e . \\ . \" " . \' ' . GNU Emacs : \a () \b backspace \d delete \f \n newline \r \t \v \nnn nnn ( ). \xHH HH ( ). . . . " '. Bash readline bind. -o emacs -o vi set ( SHELL BUILTIN COMMANDS ) . Readline Readline . inputrc set variable-name value bind ( SHELL BUILTIN COMMANDS ). readline On Off ( ). . readline "on" ( ) "1" On. Off. bind -V readline ( SHELL BUILTIN COMMANDS ). : active-region-start-color ( enable-active-region ). . . . (standout) terminfo . "\e[01;33m". active-region-end-color "undoes" active-region-start-color "normal" . . . . (standout) terminfo . "\e[0m". bell-style (audible) readline . none readline . visible readline . audible readline . bind-tty-special-chars (On) On readline readline. readline . "stty -a" bash ( cchars). blink-matching-paren (Off) On readline . colored-completion-prefix (Off) On readline . LS_COLORS. $LS_COLORS ".readline-colored-completion-prefix", readline . colored-stats (Off) On readline . LS_COLORS. comment-begin ( "#") insert-comment readline. M-# emacs # vi. completion-display-width (-1) . 0 . 0 . -1. completion-ignore-case (Off) On readline . completion-map-case (Off) On completion-ignore-case readline (-) (_) . completion-prefix-display-length (0) () . readline (...) . readline . completion-query-items (100) possible-completions. . readline readline . readline . convert-meta (On) On readline ASCII ( meta). On readline Off . LC_CTYPE . force-meta-prefix . disable-completion (Off) On readline . self-insert. echo-control-characters (On) On readline . editing-mode (emacs) readline Emacs vi. editing-mode emacs vi. emacs-mode-string (@) show-mode-in-prompt emacs . meta control . \1 \2 . enable-active-region (On) On readline . readline active-region-start-color (standout) . (bracketed-paste) . enable-bracketed-paste (On) On readline . readline . enable-keypad (Off) On readline . . enable-meta-key (On) On readline meta . Meta (0200) Meta ( meta). expand-tilde (Off) On readline (~) . force-meta-prefix (Off) On readline \M- Meta- ( Key Bindings ) \M-C Meta-C ESC C ( meta). force-meta-prefix Off () readline convert-meta : convert-meta On readline Off readline C meta (0200). history-preserve-point (Off) On previous-history next-history. history-size (unset) . . . bash HISTSIZE. history-size 500. horizontal-scroll-mode (Off) On readline . 1. input-meta (Off) On readline ( ) . Off readline On . LC_CTYPE . meta-flag input-meta. isearch-terminators ( "C-[C-j") . ESC C-j . keymap (emacs) readline . emacs, emacs-standard, emacs-meta, emacs-ctlx, vi, vi-command vi-insert. vi vi-command emacs emacs-standard. emacs editing-mode . keyseq-timeout (500) readline ( ). readline . 1000 readline . readline . mark-directories (On) On . mark-modified-lines (Off) On readline (*). mark-symlinked-directories (Off) On mark-directories. match-hidden-files (On) On readline "." ( ) . Off "." . menu-complete-display-prefix (Off) On ( ) . output-meta (Off) On readline meta. Off readline On . LC_CTYPE . page-completions (On) On readline more(1) . prefer-visible-bell bell-style. print-completions-horizontally (Off) On readline . revert-all-at-newline (Off) On readline accept-line. readline. search-ignore-case (Off) On readline . show-all-if-ambiguous (Off) . On . show-all-if-unmodified (Off) show-all-if-ambiguous. On ( ) . show-mode-in-prompt (Off) On : emacs vi command vi insertion. ( emacs-mode-string). skip-completed-text (Off) On . . readline . vi-cmd-mode-string ((cmd)) show-mode-in-prompt vi . meta control . \e1 \e2 . vi-ins-mode-string ((ins)) show-mode-in-prompt vi . meta control . \e1 \e2 . visible-stats (Off) On stat(2) . Readline Readline C . . $if $if readline. . mode mode= $if readline emacs vi. set keymap emacs-standard emacs-ctlx readline emacs. term term= . = -. xterm xterm xterm-256color . version version readline . version readline . = ( ==) != <= >= < >. ( 7.1). 0. version . application application . readline . . bash: $if Bash # "\C-xq": "\eb\"\ef\"" $endif variable variable readline. = == !=. . . on off. $else $if . $endif $if. $include . /etc/inputrc: $include /etc/inputrc Readline ( HISTORY ) . : . . readline . . emacs C-r . C-s . isearch-terminators . ESC C-j . C-g . . C-r C-s . . readline . . . Readline . C-r readline . . . Readline . . point mark set-mark. . Readline : readline active-region-start-color. enable-active-region . . beginning-of-line (C-a) . Home . end-of-line (C-e) . End . forward-char (C-f) . . backward-char (C-b) . . forward-word (M-f) . ( ). backward-word (M-b) . ( ). shell-forward-word (M-C-f) . . shell-backward-word (M-C-b) . . previous-screen-line . readline . next-screen-line . readline readline . clear-display (M-C-l) . clear-screen (C-l) . . redraw-current-line . accept-line (Newline, Return) . HISTCONTROL HISTIGNORE. . previous-history (C-p) . . next-history (C-n) . . beginning-of-history (M-<) . end-of-history (M->) . operate-and-get-next (C-o) . . fetch-history . . reverse-search-history (C-r) "up" . . . forward-search-history (C-s) "down" . . . non-incremental-reverse-search-history (M-p) . . non-incremental-forward-search-history (M-n) . . history-search-backward . . . Page Up . history-search-forward . . . Page Down . history-substring-search-backward . . . history-substring-search-forward . . . yank-nth-arg (M-C-y) ( ) . n n ( 0). n . n n "!n" . yank-last-arg (M-., M-_) ( ). yank-nth-arg . yank-last-arg ( ) . . ( ). "!$" . shell-expand-line (M-C-e) . $\*'string\*' $\*"string\*" (tilde) . . HISTORY EXPANSION . history-expand-line (M-^) . HISTORY EXPANSION . magic-space . HISTORY EXPANSION . alias-expand-line . ALIASES . history-and-alias-expand-line . insert-last-argument (M-., M-_) yank-last-arg. edit-and-execute-command (C-x C-e) . Bash $VISUAL $EDITOR emacs . end-of-file ( C-d) stty(1). readline EOF. delete-char (C-d) . tty EOF C-d . Delete . backward-delete-char (Rubout) . (kill ring). forward-backward-delete-char . quoted-insert (C-q, C-v) . C-q . tab-insert (C-v TAB) (tab). self-insert (a, b, A, 1, !, ...) . bracketed-paste-begin "bracketed paste" . readline . self-insert . . transpose-chars (C-t) . . . transpose-words (M-t) . . shell-transpose-words (M-C-t) . . shell-forward-word shell-backward-word. upcase-word (M-u) ( ) . . downcase-word (M-l) ( ) . . capitalize-word (M-c) ( ) . . overwrite-mode . . . emacs vi . readline() . self-insert . backward-delete-char . Insert . (Killing and Yanking) kill-line (C-k) (Kill) . . backward-kill-line (C-x Rubout) . . unix-line-discard (C-u) (kill-ring). kill-whole-line . kill-word (M-d) . forward-word. backward-kill-word (M-Rubout) . backward-word. shell-kill-word (M-C-d) . shell-forward-word. shell-backward-kill-word . shell-backward-word. unix-word-rubout (C-w) . unix-filename-rubout (slash) . delete-horizontal-space (M-\) . kill-region (region) . copy-region-as-kill (kill buffer) (yanked) . copy-backward-word . backward-word. copy-forward-word . forward-word. yank (C-y) . yank-pop (M-y) . yank yank-pop. digit-argument (M-0, M-1, ..., M--) . M-- . universal-argument . . universal-argument . . . complete (TAB) . Bash ( Programmable Completion ) ( $) ( ~) ( @) ( ) . . possible-completions (M-?) . readline completion-display-width COLUMNS . insert-completions (M-*) possible-completions . menu-complete complete . menu-complete . menu-complete ( bell-style) . n n . TAB . menu-complete-backward menu-complete menu-complete . . export-completions readline : o N o o S:E S E readline o "0", S:E. . ( ) S:E . N . . N S:E . . delete-char-or-list ( delete-char). possible-completions. . complete-filename (M-/) . possible-filename-completions (C-x /) . complete-username (M-~) . possible-username-completions (C-x ~) . complete-variable (M-$) . possible-variable-completions (C-x $) . complete-hostname (M-@) . possible-hostname-completions (C-x @) . complete-command (M-!) . . possible-command-completions (C-x !) . dynamic-complete-history (M-TAB) . dabbrev-expand . complete-into-braces (M-{) ( Brace Expansion ). start-kbd-macro (C-x () . end-kbd-macro (C-x )) . call-last-kbd-macro (C-x e) . print-last-kbd-macro () inputrc. re-read-init-file (C-x C-r) inputrc . abort (C-g) ( bell-style). do-lowercase-version (M-A, M-B, M-x, ...) x ( Meta) . x . prefix-meta (ESC) Meta. ESC f Meta-f. undo (C-_, C-x C-u) . revert-line (M-r) . undo . tilde-expand (M-&) (tilde expansion) . set-mark (C-@, M-) (mark) . . exchange-point-and-mark (C-x C-x) . . character-search (C-]) . . character-search-backward (M-C-]) . . skip-csi-sequence Home End. CSI (CSI) ESC [. "\e[", CSI readline . ESC [. insert-comment (M-#) comment-begin readline . : comment-begin comment-begin . . comment-begin . . spell-correct-word (C-x s) cdspell. shell-forward-word. glob-complete-word (M-g) . glob-expand-word (C-x *) . * . glob-list-expansions (C-x g) glob-expand-word . * . dump-functions readline. inputrc. dump-variables readline readline. inputrc. dump-macros readline readline. inputrc. execute-named-command (M-x) readline . . display-shell-version (C-x C-v) bash . (compspec) complete ( ) readline . bash . (compspec) . ( ) bash -E complete. -I complete ; |. . bash . bash . bash -D complete . bash . bash Completing. bash . bash actions . . -f -d bash FIGNORE . -G. . Bash FIGNORE GLOBIGNORE. -W. IFS . (metacharacters) IFS. (~) . Word Splitting. . bash -F -C. bash COMP_LINE COMP_POINT COMP_KEY COMP_TYPE . bash COMP_WORDS COMP_CWORD. ($1) ($2) ($3) . . -F . compgen compopt . COMPREPLY . -C . . (Backslash) . . bash (filter) -X . & . & . . ! bash . nocasematch bash . -P -S readline . -o dirnames complete bash . -o plusdirs complete bash . . bash readline. -o bashdefault complete bash . bash ( ) -o default complete readline . complete compopt readline . -o fullquote readline . complete . readline mark-directories readline mark-symlinked-directories readline. . complete -D. 124. 124 ( ) . . : _completion_loader() { . "/etc/bash_completion.d/$1.sh".if 0<80n \ >/dev/null 2>&1 && return 124 } complete -D -F _completion_loader.if 0<80n \ -o bashdefault -o default -o history set . HISTSIZE : HISTSIZE ( 500). ( ) HISTIGNORE HISTCONTROL. bash HISTFILE ( ~/.bash_history). . HISTFILESIZE. HISTFILESIZE . . HISTTIMEFORMAT. . bash $HISTSIZE $HISTFILE. histappend ( shopt ) bash . HISTFILE . bash HISTFILESIZE . HISTTIMEFORMAT . . HISTTIMEFORMAT . fc ( ) . history . . . HISTCONTROL HISTIGNORE . cmdhist . lithist cmdhist . shopt . csh. . +H set ( ). "set -H". . . . . . . (event) . (modifiers) . (metacharacter) . . ! . . (\) . : = . ( histchars) . !! . . . shopt ( shopt ). histverify readline . readline . readline histreedit readline . -p history . -s history . ( histchars ). . . . . ! = ( extglob shopt. !n n. !-n n. !! . "!-1". !string string. !?string[?] string. ? string . string . ^string1^string2^ . string1 string2. "!!:s^string1^string2^" ( ). !# . . . : . ^ $ * - %. 0 (). . 0 () . . n n. ^ : 1. $ . . % "?string?" . . x-y "-y" "0-y". * . "1-$". * . x* x-$. x- x-$ x* . x 0. !!. ":". . h . t . r .xxx . e . p . q . x q . q x . s/old/new/ new old . /. . old new. & new old. &. old old string !?string[?]. new old . & . g . ":s" ( ":gs/old/new/") ":&". ":s", / . a g. G "s" "&" . - -- . : true false test/[ -- . exit logout return break continue let shift - --. - -- . : [] arguments . . . [-p ] _ [] source [-p ] _ [] . ( source) filename filename. filename . . -p . path filename . PATH filename. filename . bash posix filename PATH -p. sourcepath shopt . PATH. arguments filename. . -T . (trap) DEBUG DEBUG . . DEBUG . -T DEBUG .. filename (0 ) filename . alias [-p] [[=] ...] -p alias alias name=value . name value. value . name value name. alias name ( =value ) . bg [jobspec ...] jobspec &. jobspec . bg jobspec 0 jobspec . bind [-m keymap] [-lsvSVX] bind [-m keymap] [-q function] [-u function] [-r keyseq] bind [-m keymap] -f filename bind [-m keymap] -x keyseq[:] shell-command bind [-m keymap] keyseq:function-name bind [-m keymap] -p|-P [readline-command] bind [-m keymap] keyseq:readline-command bind --readline readline readline readline. readline .inputrc '"\C-x\C-r": re-read-init-file'. readline bind. : -m _ keymap . keymap emacs emacs-standard emacs-meta emacs-ctlx vi vi-move vi-command vi-insert. vi vi-command (vi-move ) emacs emacs-standard. -l readline. -p readline bind readline. bind readline . -P readline . bind readline . -s readline bind readline. -S readline . -v readline bind readline. -V readline . -f _ filename. -q readline . -u function readline. -r _ keyseq. -x _[: ]- - keyseq. keyseq - . - readline - . readline . . - READLINE_LINE readline READLINE_POINT READLINE_MARK () . READLINE_ARGUMENT. . READLINE_LINE READLINE_POINT READLINE_MARK . -X bind . 0 . break [n] for while until select. n break n . n >= 1. n . 0 n 1. builtin shell-builtin [arguments] shell-builtin arguments . . cd . (false) shell-builtin . caller [expr] ( . source). expr caller . expr caller . . 0. 0 expr . cd [-L] [-@] [dir] cd -P [-e] [-@] [dir] dir. dir HOME dir. CDPATH dir (/) cd : CDPATH dir. CDPATH (:). CDPATH : ".". -P cd dir .. dir ( -P set). -L cd .. dir. .. dir cd dir dir dir . cd . -L -P cd -L. -e -P cd . -@ . - $OLDPWD . cd CDPATH - cd . cd PWD OLDPWD . true false . command [-pVv] command [arg ...] command . PATH . -p PATH . -V -v command command. -v command -V . -V -v . 127. command . compgen [-V varname] [option] [word] word complete -p -r -D -E -I . -V compgen varname . -F -C . . word word. true . complete [-abcdefgjksuv] [-o comp-option] [-DEI] [-A action] [-G globpat] [-W wordlist] [-F function] [-C command] [-X filterpat] [-P prefix] [-S suffix] name [name ...] complete -pr [-DEI] [name ...] name. -p . -r . -D "default" . -E "empty" . -I ; | . -D -E -I. -D -E -I name . above under Programmable Completion. . -G -W -X ( -P -S) complete. -o - - (compspec) . - : bashdefault bash compspec . default readline compspec . dirnames compspec . readline compspec ( ). . fullquote readline . noquote readline ( ). nosort readline . nospace readline () . plusdirs compspec . -A : alias . -a. arrayvar . binding Readline. builtin . -b. command . -c. directory . -d. disabled . enabled . export . -e. file readline. -f. . . -g. helptopic help. hostname HOSTFILE. job (Job names) . -j. keyword . -k. running . service . -s. setopt -o set. shopt shopt . signal (Signals). stopped . user . -u. variable . -v. -C command . -F. -F function . ($1) ($2) ($3) . function COMPREPLY. -G _ globpat . -P prefix . -S suffix . -W _ wordlist IFS . (Shell quoting) wordlist IFS. . -X _ filterpat . filterpat . ! filterpat filterpat. true -p -r -D -E -I name name . compopt [-o option] [-DEI] [+o option] [name] name options . name . option complete . -D "default" -E "empty" -I . complete . -D -E -I. true name . continue [n] continue for while until select . n bash n. n 1. n ( "top-level" ). 0 n 1. declare [-aAfFgiIlnrtux] [-p] [name[=value] ...] typeset [-aAfFgiIlnrtux] [-p] [[=] ...] . (names) . -p . -p -f -F. -p name declare . -p declare . -f . -F . extdebug shopt . -F -f. -g declare . declare . -I ( nameref) . . : -a ( above). -A ( above). -f . -i ( ARITHMETIC EVALUATION above) . -l . . -n nameref . . -n . nameref . -r name . . -t trace. DEBUG RETURN . . -u . . -x name . "+" "-" +a +A +r . declare typeset name local -g. =value value. -a -A . 0 "-f foo=bar", ( Arrays above), -f. dirs [-clpv] [+n] [-n] . . pushd popd . . : -c . -l (~) . -p . -v . +n n dirs . -n n dirs . 0 n . disown [-ar] [-h] [id ...] id . id jobspec pid id pid disown pid jobspec. -h disown SIGHUP SIGHUP. id -a -r id . id -a -r disown . 0 id . echo [-neE] [arg ...] args . 0 . -n . -e echo . -E . xpg_echo echo . echo -- . echo : \a () \b backspace \c \e \E \f \n \r \t \v \\ backslash \0nnn nnn ( ). \xHH HH ( ). \uHHHH (ISO/IEC 10646) HHHH ( ). \UHHHHHHHH (ISO/IEC 10646) HHHHHHHH ( ). echo . enable [-a] [-dnps] [-f filename] [name ...] . . -n name names. test PATH "enable -n test". name -p . . -n . -a . -s POSIX . -f filename . filename Bash BASH_LOADABLES_PATH filename. BASH_LOADABLES_PATH "." . -d -f. -s -f POSIX name enable name name "enable -f name name". 0 name . eval [arg ...] args . eval. eval 0. exec [-cl] [-a name] [command [arguments]] command . command . arguments command. -l command. login(1). -c command . -a name . command execfail. . . exec. command 0. 1. exit [n] n. n . (trap) EXIT . export [-fn] [name[=value]] ... export -p [-f] names . -f names . -n . -p export . -p -f . -p . export =value. value . export 0 names -f name . false . fc [-e ename] [-lnr] [first] [last] fc -s [pat=rep] [cmd] first last . First last ( ) ( ). first last 0 -1 -0 ( fc) 0 -1 -0 . last ( "fc -l -10" 10 ) first . first -16 . -l . -n . -r . fc ename . ename fc FCEDIT EDITOR FCEDIT. fc vi. fc . fc command pat rep. Command first . fc "r=fc"-s(dq" "r cc" "cc" "r" . first last . . cmd fc . fg [jobspec] jobspec . jobspec fg . jobspec . getopts _ [ ...] getopts . _ . . getopts name name OPTIND. OPTIND 1 . getopts OPTARG. OPTIND getopts . getopts . OPTIND name ?. getopts getopts . getopts . _ getopts . getopts . OPTERR 0 getopts _ . getopts ? name OPTARG. getopts OPTARG . getopts name (?) OPTARG . getopts name (:) OPTARG . getopts (true) . (false) . hash [-lr] [-p _] [-dt] [] hash name $PATH. name. -p hash filename . -r . PATH (hashed). -d . -t hash . -t hash . -l . -l hash . -t -d -p ( name) . . -t -p -d. name . help [-dms] [] . pattern help . : -d pattern -m pattern -s pattern pattern ( Pattern Matching ) help pattern. pattern help . help . 0 pattern. history [n] history -c history -d history -d - history -anrw [_] history -p [ ...] history -s [ ...] . * . n n . HISTTIMEFORMAT strftime(3) . history HISTTIMEFORMAT . filename history HISTFILE. filename HISTFILE -a, -n, -r, -w . : -c . . -d offset. offset -1 history -d . -d - start end . start end . -a "new" . bash . -n . bash . -r . -w . -p args . arg . -s args . args. HISTTIMEFORMAT history . . 0 offset -d -p. jobs [-lnprs] [ _ ... ] jobs -x [ ... ] . : -l . -n . -p (PID) . -r . -s . jobspec jobs . 0 jobspec . -x jobs jobspec . kill [-s sigspec | -n signum | -sigspec] id [ ... ] kill -l|-L [sigspec | exit_status] sigspec signum id. id jobspec pid. sigspec SIGKILL ( SIG ) signum . sigspec kill SIGTERM. -l . -l kill 0. exit_status -l kill . kill 128 . -L -l. kill true false . let arg [arg ...] ( above). 0 let 1 let 0. local [] [[=] ... | - ] name value. option declare. local name . local . name - local: set local . set . local . 0 local name name . logout [n] n . mapfile [-d delim] [-n count] [-O origin] [-s count] [-t] [-u fd] [-C callback] [-c quantum] [array] readarray [-d delim] [-n count] [-O origin] [-s count] [-t] [-u fd] [-C callback] [-c quantum] [] fd -u array. MAPFILE array . : -d delim . delim mapfile NUL. -n count . count 0 . -O origin. 0. -s count . -t delim ( ) . -u fd . -C callback quantum . -c quantum. -c callback. -C -c 5000. callback . callback . mapfile array . mapfile . popd [-n] [+n] [-n] . 0 dirs popd "popd +0." popd . : -n (stack) . +n n dirs . : "popd +0" "popd +1" . -n n dirs . : "popd -0" "popd -1" . -n popd cd . cd popd . popd n . popd bash dirs 0. printf [-v ] [] arguments format. -v var . : . printf(3) cCsSndiouxXeEfFgGaA printf : %b printf argument echo -e. %q printf argument . %q %Q $'' . printf . %Q %q argument . %(datefmt)T printf datefmt strftime(3). argument (epoch). : -1 -2 . -1. printf . %b %q %T ( ) . %n . %s %c l () . %S %C %ls %lc . C . . . . pushd [-n] [+n] [-n] pushd [-n] [] . pushd . : -n . +n n ( dirs ) . -n n ( dirs ) . dir dir . -n pushd cd . cd pushd . pushd . pushd n . pushd bash dirs . pwd [-LP] . -P -o physical set. -L . 0 . read [-Eers] [-a aname] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [ ...] fd -u above name name . name . . IFS ( above ). (\) . : -a _ aname 0. aname . name . -d delim . delim read NUL. -e read readline ( READLINE above) . Readline ( ) readline. -E read readline ( READLINE above) . Readline ( ) bash . -i readline read text . -n _ read nchars EOF read nchars . -N _ read nchars EOF read. read nchars . IFS ( -r ). -p prompt . -r . . ( - ) . -s . . -t _ read ( ) . . read . read name 128. 0 read . 0 EOF . -u _ fd . delim read NUL . names read REPLY. read ( 128) ( ) -u. readonly [-aAf] [-p] [[=] ...] " " names . -f name . -a -A . -A . name -p . . -p . readonly =. . 0 names -f name . return [n] (shell function) (sourced file) n . n . return (trap handler) . return DEBUG return. return . (source) n . n 8 . RETURN . return . source. set [-abefhkmnptuvxBCEHPT] [-o -] [--] [-] [ ...] set [+abefhkmnptuvxBCEHPT] [+o -] [--] [-] [ ...] set -o set +o . . posix . . . $1 $2 ... $n. : -a . -b . . -e pipeline ( ) list compound command ( SHELL GRAMMAR) above), . while until if elif && || && || ( pipefail) !. -e . ERR . ( above), . -e -e -e . -e -e . -f . -h . . -k . -m . . ( JOB CONTROL) above). . (shell) . -n . . . -o - - : allexport -a. braceexpand -B. emacs emacs. --noediting. read -e. errexit -e. errtrace -E. functrace -T. hashall -h. histexpand -H. history above HISTORY. . ignoreeof "IGNOREEOF=10" ( above). keyword -k. monitor -m. noclobber -C. noexec -n. noglob -f. nolog . notify -b. nounset -u. onecmd -t. physical -P. pipefail ( ) . . posix posix bash POSIX . SEE ALSO below posix bash. privileged -p. verbose -v. vi vi. read -e. xtrace -x. -o option-name set . +o option-name set set . -p . $ENV $BASH_ENV SHELLOPTS BASHOPTS CDPATH GLOBIGNORE . ( ) ( ) -p . -p . . -r . . -t . -u "@" "*", "@" "*", . . -v . -x simple command for case select for PS4 . -B ( above). . -C bash > >& <>. >| > . -E (trap) ERR . ERR . -H !. . -P cd . . bash . -T DEBUG RETURN . DEBUG RETURN . -- . args -. - arg . -x -v. arg . . + - . . $-. . shift [n] n+1 ... $1 .... $# $#-n+1 . n $#. n 0 . n 1. n $# . n $# 0. shopt [-pqsu] [-o] [- ...] . -o -o set . -p optnames . -p . : -s () optname. -u ( ) optname. -q ( ) optname . optname -q optnames . -o optname -o set. -s -u optname shopt . shopt ( ) . optnames . optname . shopt : array_expand_once . assoc_expand_once array_expand_once. autocd cd. . bash_source_fullpath BASH_SOURCE ( Shell Variables ). cdable_vars cd . cdspell cd . . cd . . checkhash bash . bash . checkjobs bash . bash ( JOB CONTROL above). . checkwinsize bash ( ) LINES COLUMNS . . cmdhist bash . . above HISTORY. compat31 compat32 compat40 compat41 compat42 compat43 compat44 ( SHELL COMPATIBILITY MODE below). complete_fullquote bash (metacharacters) . bash . . bash . bash 4.2. direxpand bash . readline. bash . dirspell bash . dotglob bash "." . . .. dotglob. execfail exec. exec. expand_aliases above ALIASES. . extdebug --debugger. : 1. -F declare . 2. DEBUG . 3. DEBUG 2 ( . source) return. 4. BASH_ARGC BASH_ARGV above). 5. : ( ) DEBUG RETURN. 6. : ( command ) ERR. extglob above . extquote $'string' $"string" ${parameter} . . failglob . force_fignore FIGNORE . Shell Variables above FIGNORE. . globasciiranges ( Pattern Matching above) C . b A B ASCII . globskipdots . .., ".". . globstar ** . / . gnu_errfmt GNU . histappend HISTFILE . histreedit readline . histverify readline . readline . hostcomplete readline bash @ ( Completing READLINE above). . huponexit bash SIGHUP . inherit_errexit errexit . posix. interactive_comments # ( COMMENTS above). . lastpipe . lithist cmdhist . localvar_inherit . nameref . localvar_unset unset . . login_shell ( above). . mailwarn bash bash "The mail in mailfile has been read". no_empty_cmd_completion readline bash PATH . nocaseglob bash ( Pathname Expansion above). nocasematch bash case [[ . noexpand_translation bash $"..." . . nullglob ( Pathname Expansion above) . patsub_replacement bash & Parameter Expansion above. . progcomp ( Programmable Completion above). . progcomp_alias bash . bash . promptvars PROMPTING above. . restricted_shell ( below). . . shift_verbose shift . _ . (source) PATH -p. . varredir_close {varname} ( REDIRECTION above) . xpg_echo echo . posix echo . suspend [-f] SIGCONT. -f . 0 -f. test expr [ ] 0 () 1 () expr. . above . test -- . . . test . ! expr expr . ( expr ) expr. . expr1 -a expr2 expr1 expr2 . expr1 -o expr2 expr1 expr2 . test [ . 0 arguments . (not null). ! . above . . 3 . above . -a -o . ! . ( ) . . 4 . ! . ( ) . . 5 . posix [[ < > . posix test [ ASCII. 4 (primaries). POSIX -a -o . . -a -o && || . times . 0. trap [-lpP] [[] sigspec ...] sigspec. ( sigspec ) - sigspec . (null string) sigspec. trap trap . -p action trap sigspec trap . -P sigspec. -P sigspec . -P -p trap . -l . sigspec . SIG . -l sigspec . sigspec EXIT (0) action . sigspec DEBUG action simple command for case select (( [[ for ( SHELL GRAMMAR) above). extdebug ( shopt) above) DEBUG. sigspec RETURN action . source. sigspec ERR action ( ) . ERR while until if && || && || ( pipefail) !. errexit (-e). . . . sigspec trap . true 0. type [-aftpP] name [name ...] name . -t type : alias keyword function builtin file . type . -p type $PATH "type -t name" file. -P PATH name "type -t name" file. name -p -P PATH. -a type name. (-p -P) . type (hashed) -a -p PATH name. -f command. type (true) (false) . ulimit [-HS] -a ulimit [-HS] [-bcdefiklmnpqrstuvxPRT []] . -H -S . . -H -S ulimit . limit hard soft unlimited . limit ulimit -H. . : -a . -b . -c . -d . -e ( "nice"). -f . -i . -k kqueues . -l . -m ( ). -n ( ). -p 512 ( ). -q POSIX -r . -s . -t . -u . -v . -x . -P . -R . -T . limit -a limit . -f. 1024 -t -R -p 512 -P -T -b -k -n -u posix -c -f 512 . 0 . umask [-p] [-S] [] mode. mode chmod(1). mode umask . -S mode . -p mode . mode . unalias [-a] [ ...] name . -a . name . unset [-fv] [-n] [ ...] . -v . -f . -n nameref . -n -f. . . . . BASH_ALIASES BASH_ARGV0 BASH_CMDS BASH_COMMAND BASH_SUBSHELL BASHPID COMP_WORDBREAKS DIRSTACK EPOCHREALTIME EPOCHSECONDS FUNCNAME GROUPS HISTCMD LINENO RANDOM SECONDS SRANDOM . '' . wait [-fn] [-p varname] [id ...] id id. id pid jobspec wait . ids wait $! . -n wait . 127. -p wait varname . . -n. -f wait id . ids 127. wait varname 128 SIGNALS above. id. Bash-4.0 shopt (compat31 compat32 compat40 compat41 ). -- . . . ( compat32 bash-3.2 ). compat32 . bash . (locale) [[ bash-4.1 ASCII compat32 ASCII . . . Bash-4.3 : BASH_COMPAT. ( 4.2 compatNN 42) . bash-4.4 bash . BASH_COMPAT. Bash-5.0 shopt . BASH_COMPAT bash-5.0. . compatNN NN . bash-5.0 shopt compatNN. bash-4.3 BASH_COMPAT bash-5.1 . compat31 o [[ (=~) . compat32 o < > [[ ASCII. compat40 o < > [[ ASCII. Bash bash-4.1 ASCII strcmp(3) bash-4.1 strcoll(3). compat41 o posix time ( POSIX 267). o posix word ( POSIX 221). compat42 o bash-4.2. o posix word ( POSIX 221) . compat43 o posix ( ). o (while/until/) break continue . Bash-4.4 . compat44 o BASH_ARGV BASH_ARGC . o break continue . Bash-5.0 o export readonly posix. compat50 o Bash-5.1 $RANDOM . 50 bash-5.0 RANDOM bash-5.0. o bash 5.1 . Bash-5.1 -l. compat51 o unset @ * . o ( ((...)) ) for . o [[ . o . o $((...)) . o . o test -v A[@] A . Bash-5.2 @. o ${parameter[:]=value} value ( ). Bash-5.2 . o ( shopt ) extglob ( ). extglob . extglob . compat52 o test . o -p -P bind bind . bash rbash -r . . bash : o cd. o SHELL PATH HISTFILE ENV BASH_ENV. o /. o / .. o -p . . o history. o (slash) -p hash. o . o BASHOPTS SHELLOPTS . o > >| <> >& &> >>. o exec . o -f -d enable . o enable . o -p command. o set +r shopt -u restricted_shell. . When a command that is found to be a shell script is executed (see COMMAND EXECUTION above), rbash . Bash Gnu Readline Gnu History (POSIX) 2: IEEE -- http://pubs.opengroup.org/onlinepubs/9799919799/ http://tiswww.case.edu/~chet/bash/POSIX -- posix sh(1) ksh(1) csh(1) emacs(1) vi(1) readline(3) /bin/bash bash /etc/profile ~/.bash_profile ~/.bashrc ~/.bash_logout ~/.bash_history HISTFILE bash ~/.inputrc readline bfox@gnu.org chet.ramey@case.edu bash . bash. ftp://ftp.gnu.org/pub/gnu/bash/ http://git.savannah.gnu.org/cgit/bash.git/snapshot/bash-master.tar.gz. bashbug . ! "philosophical" bug-bash@gnu.org Usenet gnu.bash.bug. : bash "recipe" bashbug . chet.ramey@case.edu. . bash sh POSIX . . "a ; b ; c" . . . ( ) . 3 . . : . GNU Bash 5.3 7 2025 BASH(1)