I have a variant of this question.
Everything was working fine on my development machine (Mac) but I had to reinstall php with homebrew because I needed the '--with-homebrew-curl' option. PHP got updated from 5.6.18 to 5.6.30. Now the old mysql functions like mysql_connect() aren't working any more, alas they are gone like as if I was using PHP 7, which I'm not. I have looked at phpinfo and see that under 'mysqlnd'->'API Extensions' it says only 'pdo_mysql,mysqli'. On my production server (where php hasn't been installed with homebrew) it says 'mysql,mysqli,pdo_mysql' and there is an own mysql section.
What has happened to the mysql-support in mysqlnd on my development machine? Can it be because it php went from 5.6.18 to 5.6.30? Can I force homebrew to install 5.6.18? Is it possible to "unlock" mysql in mysqlnd?