How can I install php_posix php extension in windows?

Question

I'm trying to play with symphony in windows, and when I run the check configuration script gives me the next error:

[[WARNING]] The posix_isatty() is available: FAILED
            *** Install and enable the php_posix extension (used to colorized the CLI output) ***

how can I install the php_posix in windows or it's not possible to install in windows?

Thanks