PHP Manual Function Reference Process Control Extensions Libevent Predefined Constants Resource Types Examples Predefined Constants The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime. EV_TIMEOUT (integer) EV_READ (integer) EV_WRITE (integer) EV_SIGNAL (integer) EV_PERSIST (integer) EVLOOP_NONBLOCK (integer) EVLOOP_ONCE (integer)