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[IDD #FYD-939827]: reading data from LDM files saved without --overwrite

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  • Subject: [IDD #FYD-939827]: reading data from LDM files saved without --overwrite
  • Date: Fri, 11 Jun 2010 13:00:01 -0600
Hi Janine,

Sorry for the tardy reply...

re:
> Hi! Thanks. I did get a few responses directly to me, so I have some
> idea of what to do.

Very good.

re:
> I do need to confirm with someone at unidata what the binary
> beginning-of-file marker is for netCDF files. I've been told it is
> "CDL1" where one is a binary one and not a char. Is this correct?

No, this is not correct.  For classic netCDF (like the files being sent
in the PCWS (aka ACARS) IDD datastream, then beginning 4 bytes will
be either CDF1 or CDF2.  CDF2 is for files with 64-bit offsets.

Here are the URLs to get you to this information in the Unidata netCDF website:

Unidata HomePage:
http://www.unidata.ucar.edu

  netCDF
  http://www.unidata.ucar.edu/software/netcdf

    Frequently Asked Questions about netCDF
    http://www.unidata.ucar.edu/software/netcdf/docs/faq.html

      How can I tell if a netCDF file uses the classic format or new 64-bit 
offset format?
      
http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#Large%20File%20Support5

> Will it uniquely identify the beginning of a netCDF file?

Yes, for netCDF classic (i.e., not netCDF4).

Cheers,

Tom
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Ticket Details
===================
Ticket ID: FYD-939827
Department: Support IDD
Priority: Normal
Status: Closed