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[netCDF #UDG-681606]: A request

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  • Subject: [netCDF #UDG-681606]: A request
  • Date: Mon, 06 Oct 2014 13:25:44 -0600
Wei,

It looks like the assertion violation you see only
occurs if the netCDF-C library is built with the
HDF5 library but without the HDF4 library. I just
tested with netCDF-4.3.2 built with --enable-hdf4
and with an HDF5 library, and it worked fine, 
with ncdump treating it as a normal netCDF-4 file.

If I try a version of netCDF-4.3.2 built with
neither the HDF4 or HDF5 library (so it only
supports netCDF-3 API), it returns an error code
indicating it's an unknown file format.

Dennis is working on a fix.

--Russ

> I have put that file on a ftp site.
> to get it:
> 
> ftp ftp.cgd.ucar.edu
> 
> Name(...): anonymous
> Password: your-email
> ftp> cd incoming
> ftp> get avhrr.hdf
> ftp> quit
> 
> Certainly this file is NOT a netcdf file.
> So, we do not expect to open it properly,
> but expect to return an error code.
> 
> Here is a short C code to reproduce the issue:
> 
> #include <stdio.h>
> #include <string.h>
> #include <netcdf.h>
> 
> #define FILE_NAME "avhrr.hdf"
> 
> /* Macro for error handling */
> #define BAIL(e) do { \
> printf("Bailing out in file %s, line %d, error:%s.\n", \
> __FILE__, __LINE__, nc_strerror(e)); \
> return e; \
> } while (0)
> 
> int main()
> {
> int ncid;
> int res;
> size_t ChunkSizeHint = 1024;
> 
> printf("open file: %s\n", FILE_NAME);
> if((res = nc__open(FILE_NAME, NC_NOWRITE, &ChunkSizeHint, &ncid)))
> BAIL(res);
> 
> printf("ncid = %d\n", ncid);
> 
> /* Close the file. */
> res = nc_close(ncid);
> 
> return 0;
> }
> 
> 
> Thanks for checking this issue.
> 
> Wei
> 
> 
> 
> 
> ================================================
> 1850 Table Mesa Dr.
> Boulder, CO 80307
> Phone: 303-497-8924
> 
> address@hidden> wrote:
> 
> > [Dennis Heimbigner intruding on this conversation]
> >
> > I do not understand how this can occur. The file type should
> > have been checked in libdispatch/dfile.c#NC_check_file_type.
> > We can fix the the assert, but I really would like to know
> > how this seemingly impossible case can occur.
> > Is there any chance of us getting a copy of that file.
> > I am guessing, that it looks like an hdf5 or hdf4 file,
> > but really isnt.
> >
> > =Dennis Heimbigner
> >   Unidata
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: UDG-681606
> > Department: Support netCDF
> > Priority: Normal
> > Status: Closed
> >
> >
> 
> 

Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: UDG-681606
Department: Support netCDF
Priority: Normal
Status: Closed