Bash/zsh keyboard shortcuts, history, aliases, functions, globbing, parameter expansion, brace expansion, misc tricks.

Modes (zsh-vi-mode)

• Esc / Ctrl+[ — insert → normal
• i / a — insert before / after cursor
• I / A — insert at start / end of line
• o — newline (multi-line edit)
• v — open current command in $EDITOR
• Cursor changes shape per mode (block in normal, beam in insert).

Movement (normal mode)

Editing (normal mode)

Operator + motion: d, c, y combine with any movement (dw, c$, yiw, …).

Text objects (with d / c / y)

iw aw i" a" i' a' i( a( i{ a{ i[ a[ i<motion> — e.g. ci" change inside quotes, daw delete around word.

Surround (zsh-vi-mode)

• S<char> — wrap visual selection
• ys<motion><char> — add surround (e.g. ysiw")
• cs<old><new> — change surround (e.g. cs"')
• ds<char> — delete surround

Control (any mode)

History

• Show: history / history 20

• Search: history | grep docker

• Interactive reverse: Ctrl+R

Expansion

• Repeat last: !!

• Run #42: !42

• Last starting with docker: !docker

• Last containing keyword: !?keyword

Reuse arguments

• Last arg: !$

• First arg: !^

• All args: !*

• By position (0 = command): !:2

• Range: !:2-4

Substitute & rerun

• Replace first in last: ^old^new

• Replace all in last: !!:gs/old/new

History config

export HISTSIZE=10000
export HISTFILESIZE=20000
export HISTCONTROL=ignoreboth
export HISTIGNORE="ls:cd:exit"
export HISTTIMEFORMAT="%F %T "
shopt -s histappend
export PROMPT_COMMAND="history -a; $PROMPT_COMMAND"

Aliases

alias ll='ls -lah'
alias ..='cd ..'
alias ...='cd ../..'
alias grep='grep --color=auto'
alias df='df -h'
alias du='du -h'
alias free='free -h'
alias mkdir='mkdir -pv'
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

• Show all: alias

• Remove (session): unalias ll

• Bypass alias: \rm file.txt / command rm file.txt

Functions

mkcd() { mkdir -p "$1" && cd "$1"; }

extract() {
    case "$1" in
        *.tar.gz|*.tgz)  tar xzf "$1" ;;
        *.tar.bz2|*.tbz) tar xjf "$1" ;;
        *.tar.xz|*.txz)  tar xJf "$1" ;;
        *.tar.zst)       tar --zstd -xf "$1" ;;
        *.tar)           tar xf "$1" ;;
        *.gz)            gunzip "$1" ;;
        *.bz2)           bunzip2 "$1" ;;
        *.xz)            unxz "$1" ;;
        *.zip)           unzip "$1" ;;
        *.7z)            7z x "$1" ;;
        *)               echo "Unknown: $1" ;;
    esac
}

fcd() { cd "$(fd -t d "$1" | head -1)"; }

bak() { cp "$1" "$1.bak.$(date +%F_%H%M%S)"; }

Globbing

• Basic wildcards:

  ls *.txt              # any .txt
  ls file?.txt          # ? = one char
  ls file[123].txt      # any of 1,2,3
  ls file[a-z].txt      # range
  ls file[!0-9].txt     # NOT digit
  

• Recursive (**) — bash needs shopt -s globstar: ls **/*.py

• Extended (shopt -s extglob):

  ls !(*.log)           # except .log
  ls +(*.jpg|*.png)     # one or more
  ls ?(a|b).txt         # optional
  ls @(*.jpg|*.png)     # exactly one
  ls *(pattern)         # zero or more
  

Zsh-specific

ls **/*.py
ls *.txt(.)           # regular files only
ls *(/)               # dirs only
ls *(@)               # symlinks only
ls *(m-7)             # modified < 7 days
ls *(Lk+100)          # > 100 KB
ls *(om[1,5])         # 5 most recent

• Null-glob (expand to nothing on no match): bash: shopt -s nullglob — zsh: setopt nullglob

Parameter expansion

${var:-default}          # use default if unset/empty
${var:=default}          # set default if unset/empty
${#var}                  # length
${var:0:4}               # substring (offset,length)
${var:5}                 # substring from offset
${var: -2}               # last 2 (note space)

Prefix/suffix removal

#/% shortest, ##/%% longest.

name="file.tar.gz"
path="/home/jo/documents/file.txt"

${name#*.}    → tar.gz
${name##*.}   → gz
${name%.*}    → file.tar
${name%%.*}   → file

${path##*/}   → file.txt   (like basename)
${path%/*}    → /home/jo/documents   (like dirname)

Replace

${name/tar/zip}          # first
${name//./,}             # all
${name/#file/doc}        # prefix
${name/%.gz/.xz}         # suffix

Case (bash 4+)

${name^^}                # all upper
${name,,}                # all lower
${name^}                 # capitalize first

Indirect / arrays

ref="name"; echo ${!ref}     # indirect

arr=(one two three)
echo ${arr[@]}               # all
echo ${#arr[@]}              # length
echo ${arr[@]:1:2}           # slice

Brace expansion

• Sequences:

  {1..10}            → 1 2 ... 10
  {a..z}
  {01..12}           # zero-padded
  {1..20..2}         # step
  

• Combinations (cartesian product): {a,b}{1,2} → a1 a2 b1 b2

• Practical:

  mkdir -p project/{src,test,docs}/{main,utils}
  cp file.txt{,.bak}            # quick backup
  mv file.{old,new}             # rename
  touch file{1..10}.txt
  

Job control

• Background: sleep 100 &

• Jobs: jobs / jobs -l

• Foreground / background: fg %1 / bg %1

• Suspend foreground: Ctrl+Z

• Detach from shell: disown %1 / disown -a

• Wait: wait / wait %1 / wait $PID

Misc tricks

• Sudo previous: sudo !!

• Last two dirs toggle: cd -

• Directory stack:

  pushd /new/dir
  popd
  dirs -v
  

• Process substitution:

  diff <(sort f1) <(sort f2)
  while read -r line; do echo "$line"; done < <(some-cmd)
  

• Redirection:

  cmd 2>/dev/null         # silence errors
  cmd 2>&1                # err → out
  cmd &> output.txt       # both to file
  cmd 2>&1 | tee log.txt  # both file + screen
  

• Here string / heredoc:

  grep "pattern" <<< "string to search"
  
  cat << 'EOF' > script.sh
  #!/bin/bash
  echo "hello"
  EOF
  

• Command substitution: echo "Today is $(date +%F)"

• Arithmetic:

  echo $((2 + 3))
  echo $((10 ** 2))
  ((count++))
  

• Time a command: time tar czf archive.tar.gz dir/

• Auto-yes / auto-no: yes | cmd / yes n | cmd