[Libburn] Re: 64 bit off_t

[Dana Jansens]

Hello,

On 2/20/06, scdbackup at gmx.net <scdbackup at gmx.net> wrote:
> Hi,
>
> > checking for special C compiler options needed for large files... no
> > [...]
> > checking for fseeko... yes
>
> Same output with my SuSE 9.0.
>
> > I have also commited a change in libburn.h that will make sure
> > _FILE_OFFSET_BITS is 64 in order to compile anything against libburn.
>
> Snaps nicely:
>  libburn/libburn.h:30:2: #error "Incompatible file offset size.
>  _FILE_OFFSET_BITS must be 64."
>
> With -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE=1 it compiles.
>
>
> > My only concern is the future, if someday 64 is not what is meant by
> > largefile, and if _FILE_OFFSET_BITS will even be set by configure on a
> > 64bit architechture. I could do weird stuff to make it dynamic to
> > whatever off_t size libburn was built with, but it wouldn't be very
> > pretty in the tree, and I am not sure if it is really necessary.
>
> There would also be the problem that applications have to follow
> any move of libburn's off_t.
> So a change of _FILE_OFFSET_BITS would make necessary a change
> in the API documentation anyway. Is the build system able to
> adjust that automatically ?

Not automatically. It's possible to do, but it would be sort of ugly,
like having libburn.h.in generate libburn.h in configure. I'd rather
if configure kept its paws out of the source files.

"Large File Support" seems to be synonymous with 64-bits. I think in
the future if larger file support is needed, it will be called
something new like "Huge File Support" or something. It'd be nice to
have someone test the build on a 64bit system, but other than the
possibility of that breaking, I think I am satisfied with how it is
now.

Dana