OS X Homebrew's PHP extensions location

Question

I Just installed homebrew/homebrew-php package, and noticed that extensions dir is actually empty, moreover, all extension directives in php.ini are commented. Despite that, phpinfo shows that all standard extensions (mysql, curl, zlib, etc.) are installed and work.

So, help me to understand, how do those extensions work without extension files and appropriate records in php.ini? How can I turn off some of standard extensions, or replace them by ones from PECL (if I need a different versions or so).

Answer 1

A short answer to an old question to avoid confusion: As of Apr 2018, Homebrew no longer supports PHP extensions, only a minimum is included with PHP. Use PECL to manage PHP extensions.