Installing/Configuring
PHP Manual

Requirements

pthreads requires a build of PHP with ZTS (Zend Thread Safety) enabled ( --enable-maintainer-zts or --enable-zts on Windows )

Caution

Zend Thread Safety cannot be enabled post build; it is a build time configuration option.

pthreads should build anywhere there is a working Posix Threads header (pthread.h) and ZTS build of PHP, including Windows (using the pthread-w32 project from redhat).