Re: Problems with C++ interface

• To: netcdfgroup@xxxxxxxxxxxxxxxx
• Subject: Re: Problems with C++ interface
• From: Gregory Orris <orris@xxxxxxxxxxxxxxxxxx>
• Date: Thu, 15 Jun 2000 10:33:10 -0400

Kristian/All,

This is actually not a problem confined to Micro!@#$, or Intel architectures.
It will also happen on Linux, Sun's and SGI's.  The problem usually stems from a
call to "new", "delete", "malloc", etc. with a zero argument, 
prior to the call to ncvarinq.  Since NetCDF++ uses the underlying NetCDF in C,
to create, inquire or destroy variables, this is usually handled via "malloc".
A mis-aligned address can cause an invalid argument to be passed to the
"malloc" call.  The failure to create space for the netcdf variable list
will then cause a string of function failures resulting in the mentioned 
message. Technically, it's not valid to call any memory allocation routine
to allocate zero bytes of memory.

At least this has been my experience, and a lot of tracing using an advanced 
debugger, to trace all addresses and calls to functions.

Hope this helps.

On Thu, Jun 15, 2000 at 11:18:54AM +0200, Kristian Senkler wrote:
> Hello all,
> 
> I got some weird problems with the C++ Interface. I'm currently using netCDF
> version 3.5beta and Microsoft Visual C++ 6.0. First, I built a dll of the
> C-Interface, second, I used this lib to build the C++-Interface. No problems
> so far.
> 
> Now, if I run the test program (example.cpp), netCDF throws a 'ncvarinq:
> ncid 3: Variable not found', and that's it.
> 
> I really don't know, what's wrong here and any help would be greatfully
> acknowledged.
> 
>       Kristian
> 
> -------
> Kristian Senkler
> Institut for Geoinformatics, University of Muenster
> Robert-Koch Str. 26 - 28, D-48149 Muenster
> tel: +49(0)251 83-3 97 61
> fax: +49(0)251 83-3 97 63
> senkler@xxxxxxxxxxxxxxxxxxxx
> www: http://ifgi.uni-muenster.de
> 

-- 
                                        Gregory J. Orris 
                                        Code 7140
                                        Naval Research Laboratory
                                        Washington, D.C. 20375
                                        tel: 202-404-4827
                                        fax: 202-404-7732
                                        e-mail: orris@xxxxxxxxxxxxxxxxxx

• References:
  • Problems with C++ interface
    • From: Kristian Senkler