Linux下全局安装composer方法

# 下载composer
[vagrant@localhost ~]$ curl -sS https://getcomposer.org/installer | php

# 将composer.phar文件移动到bin目录以便全局使用composer命令
[vagrant@localhost ~]$ mv composer.phar /usr/local/bin/composer

# 切换国内源
[vagrant@localhost ~]$ composer config -g repo.packagist composer https://packagist.phpcomposer.com