| /* Copyright (c) 2015 Google Inc. |
| * Barret Rhoden <brho@cs.berkeley.edu> |
| * See LICENSE for details. |
| * |
| * close() callbacks. |
| * |
| * Akaros has various utilities in userspace that operate on FDs, but those |
| * facilities are in the kernel in other OSs. Examples include epoll and the |
| * Rocks (socket layer). So far, these are only for compatibility. |
| * |
| * These facilities would like to know when the FD is closed. In lieu of |
| * encoding the callback info in the FD, close() will call all of the registered |
| * callbacks for every FD that closes. That's not ideal, so these facilities |
| * should only register their FD if a program actually uses the facility. |
| * |
| * To register a cb, do your own allocation of a close_cb, fill in func, then |
| * call register_close_cb. You cannot remove your CB. Concurrent calls to |
| * close() may or may not run your callback. Do not hand out an FD to a user |
| * until you have registered your CB. */ |
| |
| #pragma once |
| |
| struct close_cb { |
| struct close_cb *next; |
| void (*func)(int fd); |
| }; |
| |
| extern struct close_cb *close_callbacks; /* for use within glibc */ |
| |
| void register_close_cb(struct close_cb *cb); |
