[boost] Re: Re: Re: Re: extending boost::io

From: Jonathan Turkanis (technews_at_[hidden])
Date: 2004-10-14 12:17:59

"Jeff Garland" <jeff_at_[hidden]> wrote in message
news:20041014161315.M20378_at_crystalclearsoftware.com...
> On Thu, 14 Oct 2004 09:25:08 -0600, Jonathan Turkanis wrote
> > "Israel Fdez. Cabrera" <israel_at_[hidden]> wrote in message
> > news:416DA364.2070107_at_segurmatica.com...
> > > Jonathan Turkanis wrote:

> > > Let's think I have to use other library, i.e. libgsf  from GNU. I have
> > > the following doubt. I have a single OLE file, I open() it using a
> > > boost::io stream, how more than one stream can be obtained from a single
> > > one, taking this OLE file has more than one contained file?
> >
> > For each type of archive (zip, tar, ole) you have to have a module
> > (an 'archive_handler') that knows the format and can extract the
> > information. The appropriate handler is called automatically when
> > someone wants to read an entry for an archive of a particular type.
> > To implement a handler, however, you need to write code which either
> > completely understands the file format in question or delegates that
> > responsibility to an outside library.
>
> Well, since you guys are thinking down this path, what I've wanted to try is
> to have these "multi-stream" files export a boost::filesystem directory
> iterator for the file index and then provide an interface to open an
> individual 'sub-file' as an fstream. Of course you need the add and remove
> file interfaces as well to really get control over the archive contents.
>
> I think this may have radical impact on boost::filesystem in that this would
> be a clear case where we want 2 file system implementations available at
> runtime which is not really supported right now.

I'd love to see this too. My library (which in its present form is not nearly as
elegant or portable as Boost.Filesystem) is designed to accomodate ordinary
filesystems as well as archives. I'm about to leave for the airport, but I'd
love to continue this conversation after next week.

Best Regards,
Jonathan