an epoll file descriptor instance
a buffer that will contain triggered events
the maximum number of events to be returned ( usually size of "events" )
specifies the maximum wait time in milliseconds (-1 == infinite)
a signal set. May be specified as null, in which case epoll_pwait() is equivalent to epoll_wait().
the number of triggered events returned in "events" buffer. Or -1 in case of error with the "errno" variable set to the specific error code.
Wait for events on an epoll instance