OSX：PHP错误localhost，无法加载动态库

How can i fix this php error?

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/extensions/no-debug-non-zts-20100525/php_pdo_mysql.dll' - dlopen(/usr/lib/php/extensions/no-debug-non-zts-20100525/php_pdo_mysql.dll, 9): image not found in Unknown on line 0

I am on a mac/mavericks and I have made a mistake and did a sudo cp /private/etc/php.ini.default /private/etc/php.ini so now I get the error stated above when I run php -v