Re: [Qemu-devel] Safely reopening image files by stashing fds

[Christoph Hellwig]

On Fri, Aug 05, 2011 at 02:12:48PM +0100, Daniel P. Berrange wrote:
> > Because you cannot change O_DIRECT on an open fd :(.  This is why
> > we're going through this pain.
> 
> Hmm, I remember hearing that before, but looking at the current fcntl()
> manpage, it claims you *can* change O_DIRECT using SET_FL. Perhaps this
> is a newish feature, but it'd be nicer to use it if possible ?

It's been there since day 1 of O_DIRECT support.