Re: New copyfile system call - discuss before LSF?

Pavel Machek
2013-03-30T21:45:12Z

On Sat 2013-03-30 13:08:39, Andreas Dilger wrote:
> On 2013-03-30, at 12:49 PM, Pavel Machek wrote:
> > Hmm, really? AFAICT it would be simple to provide an
> > open_deleted_file("directory") syscall. You'd open_deleted_file(),
> > copy source file into it, then fsync(), then link it into filesystem.
> >
> > That should have atomicity properties reflected.
>
> Actually, the open_deleted_file() syscall is quite useful for many
> different things all by itself. Lots of applications need to create
> temporary files that are unlinked at application failure (without a
> race if app crashes after creating the file, but before unlinking).
> It also avoids exposing temporary files into the namespace if other
> applications are accessing the directory.

Hmm. open_deleted_file() will still need to get a directory... so it
will still need a path. Perhaps open("/foo/bar/mnt", O_DELETED) would
be acceptable interface?
Pavel
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