$ brew install zsh
$ zsh --version
zsh 5.0.7 (x86_64-apple-darwin14.0.0)
$ which zsh
/usr/local/bin/zsh
$ sudo vi /etc/shells
$ cat /etc/shells
# List of acceptable shells for chpass(1).
# Ftpd will not allow users to connect who are not using
# one of these shells.
/bin/bash
/bin/csh
/bin/ksh
/bin/sh
/bin/tcsh
/bin/zsh
/usr/local/bin/zsh
# Confirm current shell
$ echo $0
-bash
$ chsh -s '/usr/local/bin/zsh'
# Open a new tab/window
% echo $0
-zsh
Set /usr/local/bin
at first.
% cat /etc/paths
/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin
# Confirm the current shell
% cat /etc/shells
# List of acceptable shells for chpass(1).
# Ftpd will not allow users to connect who are not using
# one of these shells.
/usr/local/bin/zsh
/bin/bash
/bin/csh
/bin/ksh
/bin/sh
/bin/tcsh
/bin/zsh
% chpass -s /usr/local/bin/zsh
% chpass -s
Shell: /usr/local/bin/zsh