netCDF Perl 1.2 Announcement

Greetings!

Version 1.2 of the NetCDFPerl package is now available (but read on!).

This new version supersedes version 1.1 and has been ported to work
with both version 2 and version 3 of the netCDF package (netCDF version
3.3 was released Thursday, 1997-05-15). Sadly, NetCDFPerl version 1.1
can't simply be rebuilt against the new netCDF 3 package for reasons
elucidated below.

The ramifications for your NetCDFPerl-using scripts are as follows:

*) Your existing NetCDFPerl-using scripts will continue to work
even after you install netCDF 3 -- provided you don't then
(re)install a statically-linked perl(1) utility. This is
because the netCDF library is fully incorporated into the
installed, NetCDFPerl shared library.

*) Your existing NetCDFPerl-using scripts will continue to work
*until* you install the new NetCDFPerl release. Even then they
might continue to work -- it depends on whether or not they make
use of what should have been "hidden" symbols (read on).

If you install this new version of NetCDFPerl, then you will have to
check your NetCDFPerl-using scripts to ensure that they don't use any of
the following symbols:

ATTRIBUTE
BITFIELD
CREAT
DIMENSION
EXCL
HDIRTY
HSYNC
IARRAY
LINK
NDIRTY
NSYNC
RDWR
STRING
UNSPECIFIED
VARIABLE

The perl script will bomb with a meaningfull diagnostic message if it
does use one of the above symbols.

These symbols were mistakenly included in the NetCDFPerl public
interface (they're actually private netCDF 2 symbols that should never
have been made visible -- sigh). Since these symbols are *not* in the
netCDF version 3 public interface, any NetCDFPerl-using script that uses
any one of them will fail.

Of the above, it is extremely likely that *only* the "RDWR" symbol
will be a problem. This is because it is the only symbol that was
mistakenly used in a NetCDFPerl example and so, consequently, might
have been incorporated into NetCDFPerl-using scripts. If you replace
all instances of "RDWR" in your scripts with the correct symbol,
"NetCDF::WRITE" (using the fully-qualified form just for clarity), then
your scripts should work just fine with *either* NetCDFPerl version 1.1
*or* NetCDFPerl version 1.2.

If you use the LDM synoptic decoders from the Unidata Program Center,
then you should either

1. Patch the perl scripts -- converting all occurrences of "RDWR"
to "NetCDF::WRITE" before installing NetCDFPerl version 1.2.

or

2. Wait for the next release of the LDM synoptic decoders package
from the UPC, which will have this patch (like I said, your
existing NetCDFPerl installation and scripts will continue to
work -- even after installing netCDF 3).

This new release is available at the usual URL:

ftp://ftp.unidata.ucar.edu/pub/netcdf-perl/netcdf-perl.tar.Z

Naturally, if you have any problems, fill out our support request form --
after reading the README and INSTALL files, of course :-). We're here to
help.

Regards,
Steve Emmerson