Re: [netcdfgroup] nc-config and @NC_FLIBS@

Jim and Tomas,

> We've based our build for netcdf4 on
> nc-config --flibs
> 
> to give us the libraries needed to link netcdf to our f90 code,
> that no longer works now.
> 
> But there is a new nf-config so why can't nc-config --flibs just call
> nf-config --libs so that I don't have to make another special case for
> netcdf version handling?
> 
> If I make the switch to use pkg-config do I have any assurance that you
> will continue to support it?   We really need some stability in the tools
> we rely on.

I fixed and checked in a version of nc-config.in that the configure
script will process into a new nc-config script that uses nf-config, if
it's installed, to provide the right output for the --flibs, --fflags,
--fc, --has_f77, and --has_f90 options.

It will be in the next release, but if you want to try it out, just get

   http://svn.unidata.ucar.edu/repos/netcdf/trunk/nc-config.in

and rerun configure, make check, and make install.

Thanks for your persistence in getting this problem solved.

--Russ

> On Wed, Mar 28, 2012 at 2:50 PM, Russ Rew <address@hidden> wrote:
> 
> > Hi Thomas,
> >
> > > > shell$ nc-config --flibs
> > > > -L/some/path/lib @NC_FLIBS@
> > >
> > > Oh, I see ... there is nf-config now. I have to adapt my Makefile, then,
> > > for another case. Now it would be rather smart if nc-config would call
> > > nf-config transparently for fortran stuff, eh? Even better: What
> > > exactly is the reason not to provide files for pkg-config instead? Now
> > > we have two config scripts for NetCDF, I guess three with the C++
> > > interface. It gets messy and I wonder what for.
> > >
> > > But, well, putting a hint about nf-config in some docs would also be
> > > nice... it may be obvious, but I was not looking for it; just trying
> > > to get NetCDF re-installed quickly to get working Fortran module again
> > > (because of non-existent binary compatibility even between versions of
> > > the same compiler).
> >
> > The functionality is there, but as you've pointed out, it's not properly
> > documented and it looks like there were bugs using pkg-config for
> > netcdf-fortran.  The pkg-config files for the netCDF 4.2 C and
> > Fortran packages get installed when you invoke "make install", e.g. for
> > version 4.2 of netcdf and netcdf-fortran:
> >
> >  /usr/local/lib/pkgconfig:
> >  -rw-r--r--  1 root root  315 Mar 27 12:45 netcdf-fortran.pc
> >  -rw-r--r--  1 root root  305 Mar 26 12:37 netcdf.pc
> >
> > The C library pkg-config seems to work OK:
> >
> >  $ export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
> >  $ pkg-config --cflags --libs netcdf
> >  -I/usr/local/include  -L/usr/local/lib -lnetcdf
> >
> > I've just tidied-up the C pkg-config file and redone the Fortran file,
> > by modifying the top-level files netcdf.pc.in and netcdf-fortran.pc.in
> > in the snapshot releases for each package.  I've also documented the use
> > of pkg-config for the Fortran version 4.2 library with a couple of
> > examples in the man4/netcdf-f77.texi and man4/netcdf-f90.texi files.
> >
> > Basically it's used like this:
> >
> >  $ export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
> >  $ f90 myprogram.f90 -o myprogram `pkg-config --cflags --libs
> > netcdf-fortran`
> >
> > where here `--cflags' means *compiler* flags and `libs' requests that
> > the appropriate libraries be linked in, so it's different from the
> > nf-config options of "fflags" and "flibs", but consistent with the
> > pkg-config conventions.
> >
> > If you want to try these, you can get just the netcdf.pc.in and
> > netcdf-fortran.pc.in files from our svn tree:
> >
> >  http://svn.unidata.ucar.edu/repos/netcdf/trunk/netcdf.pc.in
> >
> > http://svn.unidata.ucar.edu/repos/netcdf-fortran/trunk/netcdf-fortran.pc.in
> >
> > Then put them in the top-level directories of the C and Fortran
> > releases, configure, make check, and make install.  The generated
> > pkg-config files get installed in the ${prefix}/lib/pkgconfig directory.
> >
> > Thanks for pointing out the problems.  Please let me know if you have
> > other improvements to suggest.  I wasn't able to figure out what was
> > meant by
> >
> > > ... nc-config would call nf-config transparently for fortran stuff
> >
> > but I think pkg-config is a more scalable solution.
> >
> > --Russ
> >
> 
> 
> 
> -- 
> Jim Edwards
> 
> CESM Software Engineering Group
> National Center for Atmospheric Research
> Boulder, CO
> 303-497-1842