Re: epoll and fork()

From: Mark Mielke (mark_at_mark.mielke.cc)
Date: 03/02/04

  • Next message: Jamey Hicks: "PATCH: add class_device_find" 
    Date:	Tue, 2 Mar 2004 10:42:02 -0500
To: Ben <linux-kernel-junk-email@slimyhorror.com>

    On Tue, Mar 02, 2004 at 12:31:20PM +0000, Ben wrote:
    > Is there a defined behaviour for what happens when a process with an epoll
    > fd forks?

    You found it. :-)

    > I've an app that inherits an epoll fd from its parent, and then
    > unregisters some file descriptors from the epoll set. This seems to have
    > the nasty side effect of unregistering the same file descriptors from the
    > parent process as well. Surely this can't be right?

    The epoll fd should probably be closed after the fork(), re-allocated,
    and then initialized to contain the file descriptors that you want to
    watch.

    mark 

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