From 1917f38a9a4173515e3f0800fbe265fb7d605b35 Mon Sep 17 00:00:00 2001 From: darksun Date: Wed, 24 Jan 2018 12:54:12 +0800 Subject: [PATCH] =?UTF-8?q?=E9=80=89=E9=A2=98:=20Linux=20/=20Unix=20Bash?= =?UTF-8?q?=20Shell=20List=20All=20Builtin=20Commands?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...ix Bash Shell List All Builtin Commands.md | 170 ++++++++++++++++++ 1 file changed, 170 insertions(+) create mode 100644 sources/tech/20130319 Linux - Unix Bash Shell List All Builtin Commands.md diff --git a/sources/tech/20130319 Linux - Unix Bash Shell List All Builtin Commands.md b/sources/tech/20130319 Linux - Unix Bash Shell List All Builtin Commands.md new file mode 100644 index 0000000000..230ca95cba --- /dev/null +++ b/sources/tech/20130319 Linux - Unix Bash Shell List All Builtin Commands.md @@ -0,0 +1,170 @@ +Linux / Unix Bash Shell List All Builtin Commands +====== + +Builtin commands contained within the bash shell itself. How do I list all built-in bash commands on Linux / Apple OS X / *BSD / Unix like operating systems without reading large size bash man page? + +A shell builtin is nothing but command or a function, called from a shell, that is executed directly in the shell itself. The bash shell executes the command directly, without invoking another program. You can view information for Bash built-ins with help command. There are different types of built-in commands. + + +### built-in command types + + 1. Bourne Shell Builtins: Builtin commands inherited from the Bourne Shell. + 2. Bash Builtins: Table of builtins specific to Bash. + 3. Modifying Shell Behavior: Builtins to modify shell attributes and optional behavior. + 4. Special Builtins: Builtin commands classified specially by POSIX. + + + +### How to see all bash builtins + +Type the following command: +``` +$ help +$ help | less +$ help | grep read +``` + +Sample outputs: +``` +GNU bash, version 4.1.5(1)-release (x86_64-pc-linux-gnu) +These shell commands are defined internally. Type `help' to see this list. +Type `help name' to find out more about the function `name'. +Use `info bash' to find out more about the shell in general. +Use `man -k' or `info' to find out more about commands not in this list. + +A star (*) next to a name means that the command is disabled. + + job_spec [&] history [-c] [-d offset] [n] or hist> + (( expression )) if COMMANDS; then COMMANDS; [ elif C> + . filename [arguments] jobs [-lnprs] [jobspec ...] or jobs > + : kill [-s sigspec | -n signum | -sigs> + [ arg... ] let arg [arg ...] + [[ expression ]] local [option] name[=value] ... + alias [-p] [name[=value] ... ] logout [n] + bg [job_spec ...] mapfile [-n count] [-O origin] [-s c> + bind [-lpvsPVS] [-m keymap] [-f filen> popd [-n] [+N | -N] + break [n] printf [-v var] format [arguments] + builtin [shell-builtin [arg ...]] pushd [-n] [+N | -N | dir] + caller [expr] pwd [-LP] + case WORD in [PATTERN [| PATTERN]...)> read [-ers] [-a array] [-d delim] [-> + cd [-L|-P] [dir] readarray [-n count] [-O origin] [-s> + command [-pVv] command [arg ...] readonly [-af] [name[=value] ...] or> + compgen [-abcdefgjksuv] [-o option] > return [n] + complete [-abcdefgjksuv] [-pr] [-DE] > select NAME [in WORDS ... ;] do COMM> + compopt [-o|+o option] [-DE] [name ..> set [--abefhkmnptuvxBCHP] [-o option> + continue [n] shift [n] + coproc [NAME] command [redirections] shopt [-pqsu] [-o] [optname ...] + declare [-aAfFilrtux] [-p] [name[=val> source filename [arguments] + dirs [-clpv] [+N] [-N] suspend [-f] + disown [-h] [-ar] [jobspec ...] test [expr] + echo [-neE] [arg ...] time [-p] pipeline + enable [-a] [-dnps] [-f filename] [na> times + eval [arg ...] trap [-lp] [[arg] signal_spec ...] + exec [-cl] [-a name] [command [argume> true + exit [n] type [-afptP] name [name ...] + export [-fn] [name[=value] ...] or ex> typeset [-aAfFilrtux] [-p] name[=val> + false ulimit [-SHacdefilmnpqrstuvx] [limit> + fc [-e ename] [-lnr] [first] [last] o> umask [-p] [-S] [mode] + fg [job_spec] unalias [-a] name [name ...] + for NAME [in WORDS ... ] ; do COMMAND> unset [-f] [-v] [name ...] + for (( exp1; exp2; exp3 )); do COMMAN> until COMMANDS; do COMMANDS; done + function name { COMMANDS ; } or name > variables - Names and meanings of so> + getopts optstring name [arg] wait [id] + hash [-lr] [-p pathname] [-dt] [name > while COMMANDS; do COMMANDS; done + help [-dms] [pattern ...] { COMMANDS ; } +``` + +### Viewing information for Bash built-ins + +To get detailed info run: +``` +help command +help read +``` +To just get a list of all built-ins with a short description, execute: + +`$ help -d` + +### Find syntax and other options for builtins + +Use the following syntax ' to find out more about the builtins commands: +``` +help name +help cd +help fg +help for +help read +help : +``` + +Sample outputs: +``` +:: : + Null command. +  + No effect; the command does nothing. +  + Exit Status: + Always succeeds +``` + +### Find out if a command is internal (builtin) or external + +Use the type command or command command: +``` +type -a command-name-here +type -a cd +type -a uname +type -a : +type -a ls +``` + + +OR +``` +type -a cd uname : ls uname +``` + +Sample outputs: +``` +cd is a shell builtin +uname is /bin/uname +: is a shell builtin +ls is aliased to `ls --color=auto' +ls is /bin/ls +l is a function +l () +{ + ls --color=auto +} + +``` + +OR +``` +command -V ls +command -V cd +command -V foo +``` + +[![View list bash built-ins command info on Linux or Unix][1]][1] + +### about the author + +The author is the creator of nixCraft and a seasoned sysadmin and a trainer for the Linux operating system/Unix shell scripting. He has worked with global clients and in various industries, including IT, education, defense and space research, and the nonprofit sector. Follow him on [Twitter][2], [Facebook][3], [Google+][4]. + +-------------------------------------------------------------------------------- + +via: https://www.cyberciti.biz/faq/linux-unix-bash-shell-list-all-builtin-commands/ + +作者：[Vivek Gite][a] +译者：[译者ID](https://github.com/译者ID) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]:https://www.cyberciti.biz +[1]:https://www.cyberciti.biz/media/new/faq/2013/03/View-list-bash-built-ins-command-info-on-Linux-or-Unix.jpg +[2]:https://twitter.com/nixcraft +[3]:https://facebook.com/nixcraft +[4]:https://plus.google.com/+CybercitiBiz