When installing PHP and MySQL on OSX  you may get the error Can’t connect to local MySQL server through socket ‘/var/mysql/mysql.sock’.  Or you may also get “No such file or directory” when calling mysql_connect from a PHP page.  This occurs because PHP is looking for the file mysql.sock in it’s typical installation location of /var/mysql/mysql.sock. However the MySQL OSX installer actually puts the file in /tmp/mysql.sock. There are two easy ways to solve the problem.

Solution 1: Create a symbolic link

Open terminal and do the following:

sudo su
mkdir /var/mysql
ln -s /tmp/mysql.sock /var/mysql/mysql.sock

You just created a symbolic link in the place where PHP expects the socket file to be located so it should be happy.

Solution 2: Edit php.ini

If you don’t like the idea of creating a symbolic link, you can also simply alter your php.ini file to point PHP to the real location of mysql.sock.

Locate /etc/php.ini. (If php.ini doesn’t exist on your system, copy /etc/php.ini.default to /etc/php.ini).  You will likely have to do this from the terminal unless you have Finder configured to show hidden files.  Open the file and update the setting mysql.default_socket so it looks like this:

mysql.default_socket = /tmp/mysql.sock

To commit the change you need to restart Apache.  You can do that in System Settings -> Sharing, then  uncheck, then recheck Web Sharing.