Question

I’m using epoll_create to wait on a socket.

What is the life-cycle of the returned resource tied to? Is there something like an epoll_destroy or is it tied to the socket’s close or destory call?

Can I re-use the result of epoll_create if close my socket and re-open a new one. Or should I just call epoll_create and forget about the previous result of epoll_create.

Answer 1

epoll_create(2) returns a file descriptor, so you just use close(2) on it when done.

Then, the idea of I/O multiplexing, often called Asynchronous I/O, is to wait for multiple events, and handle them one at a time. That means you generally need only one polling file descriptor.

epoll(7) manual page contains basic example of suggested API usage.