[Libguestfs] [PATCH libnbd] lib: Remove cookie parameter from completion callbacks.

[Richard W.M. Jones]

On Tue, Jul 30, 2019 at 11:21:25AM -0500, Eric Blake wrote:
> On 7/30/19 10:36 AM, Richard W.M. Jones wrote:
> > +When the command completes, C<callback>
> >  will be invoked as described in L<libnbd(3)/Completion callbacks>.
> > +
> 
> Do we need wording anywhere (probably in the .pod, so we only state it
> once) that mentions that the callback routine is not invoked if
> nbd_aio_FOO_callback returns -1?

I guess it's implicit from the fact that returning -1 indicates an
error.

In fact the relationship ought to be stronger than that - the command
should run if and only if nbd_aio_FOO_callback returns >= 0.  (That's
not actually true at the moment because an error can happen after
we've enqueued the command.)

Rich.

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