[netCDF #INK-865870]: Quick question about NetCDF library v4.1.1 and RH 6.3

Fernando,

> Thank you very much for your emails.
> 
> IDL has wrappers that use the API of the NetCDF 4.1.1 libraries, and when the 
> customer uses the IDL routine that creates NetCDF files gets the following 
> errors from IDL:
> 
> 'NCDF_CLOSE: Operation Failed.'
> 
> and
> 
> 'NCDF_CONTROL: Attempt to take the file out of define mode (ENDEF) failed. 
> (NC_ERROR=-31)'
> 
> though, only the (NC_ERROR=-31) is directly from  your library, correct?

Right, the -31 is NC_SYSERR, as defined in netcdf.h, which means the netCDF 
library got a system
error when calling a function such as fclose().  The global integer errno 
should be set to a system
error code that indicated something more specific than "operation failed", and 
if IDL had called
nc_strerror, to convert the error code into a string, it should have provided 
the more specific 
message.  Typically, calling close with a bad file descriptor or having an 
uncommitted write 
encounter an I/O error are the kinds of things that can cause close to fail.

> The key issue here is that it only happens in their version of Red Hat 6.3, 
> and does not happen in other flavors of Linux. And not just any version of RH 
> 6.3, but that with the kernel version that I sent you in my previous email. I 
> have tested his code with a "vanilla" version of RedHat 6.3 and I was not 
> able to reproduce the problem!.

That's strange, we haven't seen anything like that.

> That's why I was wondering if there was a know issue with that particular 
> kernel in RH.

Nope.

> I will pass on to my customer your comments and see if he can understand what 
> was updated in his system or try to debug the issue from inside IDL.
> 
> Thanks again for your help. If you don't mind, if the customer has another 
> questoin related with NetCDF libraries, may I ask you again?

Sure, feel free to send any questions to address@hidden.

--Russ

> Cheers!
> Fernando
> 
> 
> 
> -----Original Message-----
> From: Unidata netCDF Support [mailto:address@hidden]
> Sent: Sunday, June 09, 2013 2:59 PM
> To: Fernando Santoro
> Cc: address@hidden; Berangere Casson
> Subject: [netCDF #INK-865870]: Quick question about NetCDF library v4.1.1 and 
> RH 6.3
> 
> Fernando,
> 
> Oops, please ignore that last answer.  I was thinking you were relying on a 
> customer netCDF 4.1.1 installation, but I'm sure you were really referring to 
> a static installation of netCDF 4.1.1 in one of your products.
> 
> > > I'm a tech support engineer at Exelis VIS, the company that develops
> > > ENVI and IDL here in Boulder.
> > >
> > > I have a quick question. Is there any known incompatibility between
> > > the NetCDF library version 4.1.1 and Red Hat 6.3 (Linux eld467
> > > 2.6.32-279.19.1.el6.x86_64).
> 
> I've never heard of such an incompatibility, but we actually don't test on 
> Red Hat Linux here, but just various versions of Fedora between 14 and 18, 
> and haven't encountered any differences that were due to the version of 
> Fedora.  We also test the same source on various other versions of Linux and 
> Unix, including Solaris and Mac OS-X.
> 
> > > I'm asking this because I have a customer that has created an IDL
> > > code to create NetCDF files in a loop, and after some iterations the
> > > code crashes when creating the NetCDF file. I have tested the same
> > > code with the same NetCDF library version on a Red Hat 6.0 machine,
> > > and everything works fine.
> 
> We have fixed some memory leaks in more recent versions of netCDF since 
> 4.1.1, but nothing very serious.  Does the code crash with insufficient 
> memory?  Did a core dump reveal it was in the netCDF library, and if so, in 
> what function?
> 
> --Russ
> 
> Russ Rew                                         UCAR Unidata Program
> address@hidden                      http://www.unidata.ucar.edu
> 
> 
> 
> Ticket Details
> ===================
> Ticket ID: INK-865870
> Department: Support netCDF
> Priority: Normal
> Status: Closed
> 
> 
Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: INK-865870
Department: Support netCDF
Priority: Normal
Status: Closed