Programming Tips - Bash: get help for a specific builtin command

Date: 2022jul5 Language: bash OS: Linux Q. Bash: get help for a specific builtin command A. Use `help`. For example to get info about the `test` command:
help test help test | less
This gets info about [[ .. ]] Help alone will list all the builtin commands:
help
GNU bash, version 5.1.16(1)-release (x86_64-redhat-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 [-d delim] [-n count] [-O or> bind [-lpsvPSVX] [-m keymap] [-f file> 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 [-e]] [-@]] [dir] readarray [-d delim] [-n count] [-O > command [-pVv] command [arg ...] readonly [-aAf] [name[=value] ...] o> compgen [-abcdefgjksuv] [-o option] [> return [n] complete [-abcdefgjksuv] [-pr] [-DEI]> select NAME [in WORDS ... ;] do COMM> compopt [-o|+o option] [-DEI] [name .> set [-abefhkmnptuvxBCHP] [-o option-> continue [n] shift [n] coproc [NAME] command [redirections] shopt [-pqsu] [-o] [optname ...] declare [-aAfFgiIlnrtux] [-p] [name[=> source filename [arguments] dirs [-clpv] [+N] [-N] suspend [-f] disown [-h] [-ar] [jobspec ... | pid > 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 [-aAfFgiIlnrtux] [-p] name[=> false ulimit [-SHabcdefiklmnpqrstuvxPT] [l> 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] [-n] [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 [-fn] [-p var] [id ...] hash [-lr] [-p pathname] [-dt] [name > while COMMANDS; do COMMANDS; done help [-dms] [pattern ...] { COMMANDS ; }
This is much esier that doing `man bash` and seaching in there