On Fri, Nov 27, 2009 at 11:24:37PM +0100, Nicolas Cellier wrote:
> 
> I wonder why level 3 stdio was used (FILE * fopen, fclose ...) rather
> than level 2 (int fid, open, close, ...) in file plugin... Better
> portability ?
> 
> Nicolas

This is an interesting question, and I wonder if anyone has ever measured
the difference between the two approaches.

In the Windows VM, FilePlugin uses the standard win32 interface interacting
with HANDLE rather than (FILE *). The other VMs use stdio in the file
plugin. Loosely speaking, the Windows VM is using "level 2", while the
other VMs are working at "level 3".

Has anyone ever measured the file IO performance of an image running
on the Windows VM versus a Unix or Mac VM on the same hardware? The
plugin could be written in either manner on any of the platforms, so
it would be interesting to know if one approach delivers better overall
results than the other.

Dave