Re: Is OpenFile asynchronous

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while the createfile operation is synchronous you can on vista cancel the
createfile request from another thread using CancelSynchronousIo or
CanncelIoEx...but the driver which is implementing the create file request
must support cancelation as well, so it will not always work.

d

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"Skywing [MVP]" <skywing_NO_SPAM_@xxxxxxxxxxxxxxxxxxx> wrote in message
news:%23r3apiDrGHA.4336@xxxxxxxxxxxxxxxxxxxxxxx
It may be expensive if the the file is opened through the redirector over
the network or through a slow I/O device like a CDROM that might need to
seek for awhile if it already has a large request queue.

--
Ken Johnson (Skywing)
Windows SDK MVP

"anton bassov" <soviet_bloke@xxxxxxxxxxx> wrote in message
news:1153425434.049251.153540@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi mate

Why do you think you need to open a file asynchronously, in the first
place???? Please note that my question has nothing to do with IO
operations on file - you may want asynchronous IO, but why opening
handles asynchronously???? After all, opening the existing file is not
really a time-consuming operation, is it?

Anton Bassov


William DePalo [MVP VC++] wrote:
<jondelac@xxxxxxxxx> wrote in message
news:1153365522.921473.33930@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I am trying to find out of OpenFile is async or can be made async... I
want to open a file over a network share and dont want to wait till
the
file opens... How can I do this?

No, not only is it is not asynchronous, it is deprecated. You should use
CreateFile() instead. But that's not async, either. Can't you just call
the
function in another thread?

Regards,
Will





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