mac下安装mysql 连接时候报错 ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

http://segmentfault.com/q/1010000000094608
同样的问题，先在网上搜了下其他人解决这个问题的方法，是去修改mysql.cnf文件添加mysql.sock文件路径，再搜了一下我的mac没有mysql.cnf，也没有mysql.sock文件。
在查看mysql的安装说明ReadMe.txt中有个启动方法

If you have installed the Startup Item, use this command:

 shell> sudo /Library/StartupItems/MySQLCOM/MySQLCOM start
 (ENTER YOUR PASSWORD, IF NECESSARY)
 (PRESS CONTROL-D OR ENTER "EXIT" TO EXIT THE SHELL)
If you don't use the Startup Item, enter the following command sequence:

 shell> cd /usr/local/mysql
 shell> sudo ./bin/mysqld_safe
 (ENTER YOUR PASSWORD, IF NECESSARY)
 (PRESS CONTROL-Z)
 shell> bg
 (PRESS CONTROL-D OR ENTER "EXIT" TO EXIT THE SHELL)
使用sudo的时候会让你输入你的登陆密码。
这样就可以启动
[chopin:~:22:47:07]$ sudo /Library/StartupItems/MySQLCOM/MySQLCOM start
Password:
Starting MySQL database server

[chopin:~:22:52:06]$ mysql
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 1
Server version: 5.1.63 MySQL Community Server (GPL)

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