Awesome ZSH

This document briefly covers ZSH shell and serves as a quick summary of its many features. It's not a full guide nor a detailed documentation. It's merely a scratchpad from my journey into ZSH.

Document assumes moderate knowledge of Bash shell.

Enable ZSH

$ chsh -s /bin/zsh         # setting zsh as default shell
                           # or simply use oh-my-zsh installer

Completions

% autoload -U compinit && compinit
% cp -<TAB>
% kill <TAB>

ZSH on steroids (oh-my-zsh installed)

• Install oh-my-zsh from github
• Update configuration to your needs in ~/.zshrc
• Put custom configuration in ~/.oh-my-zsh/custom

Extended globing & qualifiers

% echo *        # like in bash
% echo **/*     # glob recursively
% echo **/*(.)  # glob recursively (just files)
$ echo **/*(/)  # glob recursively (just directories)

Redirects

% echo Hello >a.txt >&1         # print Hello to both a.txt and stdout
% echo Hello >a.txt >/dev/fd/0  # same
$ echo hello | tee a.txt        # same thing in bash
% echo Hello >a.txt >b.txt      # print Hello to both a.txt and b.txt

Auto change directories

~% coding
coding% 

% unsetopt auto_cd      # to disable

Expand paths

~% cd c/w/m/i<TAB>
~% cd coding/work/mobile/ios

but if path is not unique:

~% cd c/w<TAB>
~% cd coding/w
work  week  wrong

Path replacement

~% cd /usr/local/bin
/usr/local/bin% cd bin share
/usr/local/share%

Expand variables

~% echo %PATH<TAB>
~% echo /opt/local/bin:/opt/local/sbin:/usr/bin:/bin:/usr/sbin:/sbin

% vared PATH         # load PATH variable into line editor, ENTER to accept

Approximated completion

# ~/.oh-my-zsh/custom/completions.zsh
# Allow aproximation when completing
zstyle ':completion:::::' completer _complete _approximate
zstyle ':completion:*:approximate:*' max-errors 2

then try it out:

~% cd codign/wo<TAB>
~% cd coding/work/

~% cp --reg<TAB>
~% cp --recursively

SSH remote hosts

~% ssh user@m<TAB>
~% ssh user@myserver.com

Remote path completion

~% git clone myserver.com:/home/user/<TAB>
~% git clone myserver.com:/home/user
repo-a.git  repo-b.git  repo-c.git

Iterating over files

$ for f in *.txt; do echo $f; done  # bash
% for f (*.txt) { echo $f; }        # same thing in zsh

Renaming

% autoload -U zmv                    # load zmv first
% zmv '(*).txt' '$1.html'
% zmv -n '(*).txt' '$1.html'
% zmv -n '(**/)(*).txt' '$1/$2.html'

More examples at zshwiki.

History navigation

% zmv <UP>      # it will only iterate over history elements starting with zmv

Better history navigation

If you have oh-my-zsh installed then enable history-substring-search plugin (~/.zshrc):

plugins=(history-substring-search ...)	

You'll get even better context history navigation (with colors).

Locating stuff

% which echo ls sh
% whence echo ls sh
% echo =ls	

Various Prompts

Modify ~/.zshrc from:

ZSH_THEME="robbyrussell"

to

ZSH_THEME="random"

Each new zsh will get random theme. You can see them all at wiki.

Custom hooks

# ~/.oh-my-zsh/custom/utils.zsh
# directory change hook
#
function chpwd; {
    if [[ "$PWD" == "/etc" ]]; then
	    echo "You have entered /etc, don't break anything!"
    fi
}

Then try it out:

~% cd /etc
You have entered /etc, don't break anything!
/etc%	

Reference

1. oh-my-zsh
2. ZSH Tips by ZZapper
3. 10 zsh tricks you may not know...
4. ZSH documentation
5. Advanced Bash programming
6. Shell programming with bash: by example, by counter-example

License

Document released under Attribution-NonCommercial-ShareAlike 4.0 International. In other words: noncommercial, requires attribution and must be reproduced with a similar license.