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[netCDF #DSM-235963]: nc__open() bufrsizehintp question

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  • Subject: [netCDF #DSM-235963]: nc__open() bufrsizehintp question
  • Date: Thu, 13 Feb 2014 08:49:16 -0700
Hi Charlie,

Sorry for the slow response, I'm still catching up from a week off.

> I'm confused by the bufrsizehintp argument returned by nc__open().
> When I open a netCDF3 file, bufrsizehintp returns with a normal value,
> e.g., 4096. However, when I open a netCDF4 file, bufrsizehintp returns
> with the value zero, always. Is this expected? Should I worry?

It's expected and you shouldn't worry, though it would be nice if it
were also documented.  That argument is ignored for netCDF-4 files, as
it isn't even passed from NC4_open() to nc4_open_file() (both in 
libsrc4/nc4file.c), where the file actually gets opened.

The nc__open() function documentation should include this caution
that appears in the nc__enddef() documentation:

  Caution: this function exposes internals of the netcdf version 1 
  file format. Users should use nc_enddef in most circumstances. 
  This function may not be available on future netcdf implementations.

--Russ

> I never noticed this before and want to be sure I'm not making
> incorrect assumptions.
> 
> Thanks!
> Charlie
> --
> Charlie Zender, Earth System Sci. & Computer Sci.
> University of California, Irvine 949-891-2429 )'(
> 
> 
Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: DSM-235963
Department: Support netCDF
Priority: High
Status: Closed