1.首先登录MySQL命令行，查看unix socket所在目录。
mysql> STATUS
--------------
/usr/local/mysql/bin/mysql Ver 14.14 Distrib 5.7.15, for osx10.11 (x86_64) using EditLine wrapper
Connection id: 2
Current database: todo_list
Current user: root@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ‘‘
Using delimiter: ;
Server version: 5.7.15 MySQL Community Server (GPL)
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: latin1
Db characterset: latin1
Client characterset: utf8
Conn. characterset: utf8
UNIX socket: /tmp/mysql.sock
Uptime: 10 hours 53 min 25 sec
2. 根据phpinfo()查看 PHP.ini的目录和找到mysql.default_socket、mysqli.default_socket、pdo_mysql.default_socket的所在目录。mac下php.ini默认的目录是/private/etc/php.ini.
若mysql.default_socket、mysqli.default_socket、pdo_mysql.default_socket的值不是步骤1中的/tmp/mysql.sock，则修改php.ini中的mysql.default_socket、mysqli.default_socket、pdo_mysql.default_socket值为 /tmp/mysql.sock
若/private/etc/php.ini不存在，则复制一个
cp /private/etc/php.ini.default /private/etc/php.ini
3. 重启apache
sudo apachectl restart
reference: http://www.cnblogs.com/whlives/p/4495106.html
mac 连接mysql提示 mysqli::real_connect(): (HY000/2002): No such file or directory
原文：http://www.cnblogs.com/ganghuige/p/6414458.html