destination array for the reported events
timeout in ms or -1 to disable timing out
on success the number of file descriptors for which at least one event was reported. 0 indicates that this call timed out before an event on any file descriptor occurred. On error -1 is returned and errno set appropriately.
Calls epoll_wait() using the current epoll file descriptor.
events.length specifies the maximum number of file descriptors for which events can be reported with this epoll_wait() call.
The current epoll file descriptor should have been sucessfully obtained by create() or epoll_create1() and not already been closed, otherwise epoll_ctl() will fail so that this method returns -1.