Returns true if the client's file handle is registered with epoll for
the events specified with the client reference as attachment. Returns
false if the client's file handle is not registered with epoll or, when
multiple instances of the implementing class share the same file handle,
if it is registered with another instance.
Note that the returned value can be true by mistake when epoll
unexpectedly unregistered the file descriptor as it happens when the
file descriptor is closed (e.g. on error). However, the returned value
cannot be true by mistake.
Returns true if the client's file handle is registered with epoll for the events specified with the client reference as attachment. Returns false if the client's file handle is not registered with epoll or, when multiple instances of the implementing class share the same file handle, if it is registered with another instance.
Note that the returned value can be true by mistake when epoll unexpectedly unregistered the file descriptor as it happens when the file descriptor is closed (e.g. on error). However, the returned value cannot be true by mistake.