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Re: 19990223: netCDF on Unix and Windows

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  • Subject: Re: 19990223: netCDF on Unix and Windows
  • Date: Wed, 24 Feb 1999 11:01:27 -0700
>To: address@hidden
>From: "Charlease L. Bobo" <address@hidden>
>Subject: netCDF on Unix and Windows
>Organization: Mission Research Corporation
>Keywords: 199902231937.MAA09071

Charlease,

Another reason your MSDOS netCDF library may not be able to read the
file created on the SGI platform occurred to me this morning.

Depending on the C compiler flags used to compile a library on MSDOS,
it may support only a 16-bit int data type. Very early versions of the
netCDF library declared dimension sizes and offsets to be type "int"
rather than type "size_t", so on MSDOS all dimensions sizes and
indices were limited to 16-bit integers.  Hence variables larger than
2^15 = 32768 could not be accessed.  Small netCDF datasets used in
test cases would work OK, but large datasets could not be accessed.

If the PV-WAVE library was compiled with a small memory model or from
early netCDF sources that declared dimension indices to be of type int
rather than size_t, it could not read netCDF files with large
variables (more than 32768 values).

Another possibility is that the PV-WAVE library is OK for large
datasets, but you are using 64-bit offsets on your SGI in really huge
datasets (larger than 2 Gbytes).  Such huge files cannot be read on
any platform that doesn't support 64-bit file offsets ...

--Russ

_____________________________________________________________________

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