POSIX
PHP Manual

Введение

This module contains an interface to those functions defined in the IEEE 1003.1 (POSIX.1) standards document which are not accessible through other means.

Внимание

Sensitive data can be retrieved with the POSIX functions, e.g. posix_getpwnam() and friends. None of the POSIX function perform any kind of access checking when safe mode is enabled. It's therefore strongly advised to disable the POSIX extension at all (use --disable-posix in your configure line) if you're operating in such an environment.

Замечание: Для Windows-платформ это расширение недоступно.


POSIX
PHP Manual