TSRMLS_* keywords in PHP source

Hello! What role does the keywords TSRMLS_CC, TSRMLS_DC, TSRMLS_D have when passed along with a argument in PHP's source? For example in this random file: http://lxr.php.net/opengrok/xref/PHP_5_4/ext/intl/formatter/formatter_data.c I don't even know if "keyword" is the right technical term for it because it's the first time I see this kind of call in C: foo(data_type variable_name "keyword"); -- Barbu Paul - Gheorghe Common sense is not so common - Voltaire Visit My GitHub profile to see my open-source projects - https://github.com/paullik