Re: API/ABI rank of headers in /usr/include/isofs/cd9660

[David Holland <dholland-tech%netbsd.org@localhost>]

On Tue, May 13, 2014 at 10:36:08PM +0200, Thomas Schmitt wrote:
 > > There are some that may be useful for userland applications
 > > to grovel through the physical format,
 > 
 > <isofs/cd9660/iso.h> could be seen as such a thing. udf exposes
 > the equivalent, ecma167-udf.h.
 > But any interested application can just copy it into its own
 > source tree, if it wants record layouts and number conversion
 > macros.
 > So i will propose to remove iso.h from the public list.
 > It will not hamper my own plans, though, if it is kept public.

In an ideal world, each filesystem would install two headers:

 - one with the structures, constants, etc. needed to work with the
on-disk format; this would be used by fsck, newfs, makefs, etc.

 - one with the mount arguments structure, related flags, and anything
else needed to operate mount(2) for the fs in question; this would be
used by mount.

All the other stuff (in-memory structures, function prototypes, etc.)
should be in other headers that aren't installed for userland.

Most of our filesystems are a long way from this ideal world. For that
matter, some don't even really distinguish their on-disk and in-memory
structures properly. (*cough* ffs)

-- 
David A. Holland
dholland%netbsd.org@localhost