what is the difference between EPOLL File descriptor and event file descriptor?

Question

i am using EPOLL and eventfd for IPC in threads but i am not getting the differences between the arguments epoll file descriptor and event file descriptor

can you please elaborate...

thank you.

Answer 1

epoll file descriptor : system call :

      int epoll_create1(int flags);  

returns the epoll file descriptor, also called efd. This descriptor is use for polling(epoll_wait) and control(epoll_ctl) commands.

event file descriptor : Normal socket fd return from socket or accept like system calls knows as event file descriptor. These file descriptors are set events like EPOLLIN, EPOLLOUT ,EPOLLET etc..

event file descriptors are register or bind on event file descriptor for polling the events.