None of the posix_* functions are available under Windows, since Windows is not POSIX compliant. But there seems to be / was an optional software package available, see here: https://en.wikipedia.org/wiki/Microsoft_POSIX_subsystem
(PHP 4, PHP 5, PHP 7, PHP 8)
posix_getuid — Devolver el ID real de usuario del proceso actual
Devuelve el ID real numérico de usuario del proceso actual.
Devuelve el id de usuario, como valor de tipo integer
Ejemplo #1 Ejemplo de uso de posix_getuid()
<?php
echo posix_getuid(); //10000
?>
None of the posix_* functions are available under Windows, since Windows is not POSIX compliant. But there seems to be / was an optional software package available, see here: https://en.wikipedia.org/wiki/Microsoft_POSIX_subsystem