C version of NXbrowse

[Ray Osborn]

Happy New Millenium to one and all!  Since nobody seems to have been
affected by the millenium bug (except for web sites showing the year as
19100), I'm not so disappointed that I didn't make a big deal about NeXus
Y2k compatibility.

Just a quick explanation of the changes to NAPI.C.  I have rewritten the
NeXus browser, NXbrowse, entirely in C because I think it's useful to have
at least one browser that can be guaranteed to work on all platforms, and I
know a lot of you haven't installed Fortran 90 compilers.  I have tested it
on Alpha/VMS, Linux, and the Mac (yes, Mark, there is standard terminal
emulation even on Macs).  Please try it out and let me know if you encounter
any problems.

Since you can't guarantee that a group search using NXgetnextentry will not
be restarted before it's been completed, I needed a way to reinitialize it,
so I've written NXinitgroupdir (and NXinitattrdir).  I would be grateful if
Mark (or Przemek) could confirm that it doesn't do anything pathological.
It simply calls NXIKillDir, which only frees pointers if they've been
allocated before, and NXIInitDir, so I think it's safe.  I do the same for
the attribute searches.

NXgetgroupinfo and NXgetattrinfo return the number of groups and attributes
respectively.  NXgetgroupinfo also returns the name and class of the
currently open group.  I found this useful when writing Fortran 90 routines
to search for other linked data items.

One useful feature of adding these functions is that they now remove the
necessity for the Fortran 90 API to know the internal details of the
NXhandle struct.  If everyone accepts these changes, I will modify the F90
API accordingly.

Regards,
Ray
-- 
Dr Ray Osborn                Tel: +1 (630) 252-9011
Materials Science Division   Fax: +1 (630) 252-7777
Argonne National Laboratory  E-mail: ROsborn at anl.gov
Argonne, IL 60439-4845