# zsh — the Z Shell with Powerful Globbing and Completion > Use zsh productively: globbing, glob qualifiers, arrays, completion, setopt and Oh My Zsh – the Z shell beyond plain bash. Source: https://www.jpkc.com/db/en/cheatsheets/shell-system/zsh/ zsh (the Z shell) is largely bash-compatible but adds serious power on top: rich tab completion, recursive globbing with glob qualifiers, 1-based arrays and a long list of `setopt` switches. It has been the default shell on macOS since Catalina; on Linux you switch with `chsh -s $(which zsh)`. Frameworks like Oh My Zsh and Prezto ship themes, plugins and sensible defaults out of the box. This guide focuses on the features that make zsh more productive than plain bash. ## Globbing & Pattern Matching `ls **/*.txt` — Recursive globbing. Match files in all subdirectories (enabled by default). ```bash ls **/*.json ``` `ls *(.)` — Glob qualifier: match only regular files. ```bash ls -la *(.) ``` `ls *(/)` — Glob qualifier: match only directories. ```bash ls -d *(/) ``` `ls *(@)` — Glob qualifier: match only symbolic links. ```bash ls -la *(@) ``` `ls *(om[1,5])` — Glob qualifier: 5 most recently modified files. o=order, m=mtime. ```bash ls -la *(om[1,5]) ``` `ls *(Lk+100)` — Glob qualifier: files larger than 100 KB. L=size, k=KB, +=greater. ```bash ls -lh *(Lk+100) ``` `ls *(.mh-1)` — Glob qualifier: files modified in the last hour. m=mtime, h=hours. ```bash ls -la *(.mh-1) ``` `ls (#i)pattern` — Case-insensitive glob matching (requires EXTENDED_GLOB). ```bash setopt EXTENDED_GLOB; ls (#i)readme* ``` `ls ^pattern` — Negation glob. Match everything except pattern (requires EXTENDED_GLOB). ```bash setopt EXTENDED_GLOB; ls ^*.log ``` ## Parameter Expansion `${(U)VAR}` — Convert string to uppercase. ```bash name='hello'; echo "${(U)name}" # HELLO ``` `${(L)VAR}` — Convert string to lowercase. ```bash NAME='WORLD'; echo "${(L)NAME}" # world ``` `${(C)VAR}` — Capitalize first letter of each word. ```bash str='hello world'; echo "${(C)str}" # Hello World ``` `${(s:sep:)VAR}` — Split string into an array by separator. ```bash PATH_PARTS=(${(s/:/)PATH}); echo "${PATH_PARTS[1]}" ``` `${(j:sep:)ARRAY}` — Join array elements with separator. ```bash arr=(a b c); echo "${(j:,:)arr}" # a,b,c ``` `${(t)VAR}` — Show the type of a variable (scalar, array, integer, etc.). ```bash arr=(1 2 3); echo "${(t)arr}" # array ``` `${(u)ARRAY}` — Remove duplicate elements from an array (unique). ```bash arr=(a b a c b); echo "${(u)arr}" # a b c ``` `${(o)ARRAY} / ${(O)ARRAY}` — Sort array in ascending / descending order. ```bash arr=(cherry apple banana); echo "${(o)arr}" ``` ## Arrays & Associative Arrays `arr=(val1 val2 val3)` — Declare an indexed array. Zsh arrays are 1-based (not 0-based like Bash). ```bash colors=(red green blue); echo "$colors[1]" # red ``` `echo "$arr[1]"` — Access first element (1-based indexing, unlike Bash). ```bash echo "$colors[2]" # green ``` `echo "$arr[-1]"` — Access last element using negative index. ```bash echo "$colors[-1]" # blue ``` `echo "$arr[2,4]"` — Array slice from index 2 to 4 (inclusive). ```bash nums=(10 20 30 40 50); echo "$nums[2,4]" # 20 30 40 ``` `typeset -A map` — Declare an associative array. ```bash typeset -A ports; ports=(http 80 https 443) ``` `echo "${(k)map}"` — Get all keys of an associative array. ```bash echo "${(k)ports}" # http https ``` `echo "${(kv)map}"` — Get all key-value pairs of an associative array. ```bash echo "${(kv)ports}" # http 80 https 443 ``` ## History & Navigation `Ctrl+R` — Incremental reverse history search. ```bash Ctrl+R, then type to search ``` `!!` — Repeat the last command. ```bash sudo !! ``` `!$` — Last argument of the previous command. ```bash mkdir mydir; cd !$ ``` `!*` — All arguments of the previous command. ```bash echo foo bar baz; echo !* ``` `!` — Run the most recent command starting with string. ```bash !docker ``` `fc` — Open last command in $EDITOR for editing and re-execution. ```bash fc ``` `history 1` — Show full command history (Zsh numbers from 1). ```bash history 1 | grep ssh ``` `setopt SHARE_HISTORY` — Share history between all running Zsh sessions. ```bash setopt SHARE_HISTORY ``` ## Tab Completion `Tab` — Complete command, path, or argument. Shows menu on ambiguity. ```bash git che # completes to git checkout ``` `Tab Tab` — Cycle through completion options in menu. ```bash cd /u # cycles through /usr, /Users, etc. ``` `compinit` — Initialize the completion system. Usually in .zshrc. ```bash autoload -Uz compinit && compinit ``` `zstyle ':completion:*' menu select` — Enable interactive menu selection for completions. ```bash zstyle ':completion:*' menu select ``` `zstyle ':completion:*' matcher-list 'm:{a-z}={A-Z}'` — Enable case-insensitive tab completion. ```bash zstyle ':completion:*' matcher-list 'm:{a-z}={A-Z}' ``` ## Shell Options (setopt) `setopt AUTO_CD` — Type directory name to cd into it (no cd needed). ```bash setopt AUTO_CD; /tmp # same as cd /tmp ``` `setopt CORRECT` — Enable spelling correction for commands. ```bash setopt CORRECT; gti status # suggests: git? ``` `setopt CORRECT_ALL` — Enable spelling correction for commands and arguments. ```bash setopt CORRECT_ALL ``` `setopt NO_CASE_GLOB` — Make globbing case-insensitive. ```bash setopt NO_CASE_GLOB; ls *.TXT # matches .txt too ``` `setopt EXTENDED_GLOB` — Enable extended globbing operators (^, ~, #). ```bash setopt EXTENDED_GLOB; ls ^*.log ``` `setopt GLOB_DOTS` — Include dotfiles in glob matches without explicit dot. ```bash setopt GLOB_DOTS; ls * ``` `setopt HIST_IGNORE_DUPS` — Do not save duplicate commands in history. ```bash setopt HIST_IGNORE_DUPS ``` `setopt HIST_IGNORE_SPACE` — Do not save commands that start with a space. ```bash setopt HIST_IGNORE_SPACE; echo 'secret' ``` `setopt APPEND_HISTORY` — Append to history file instead of overwriting. ```bash setopt APPEND_HISTORY ``` `unsetopt