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