Where to get OPeNDAP client libraries

If you want to run an OPeNDAP-enabled version of NCL, then you may first need to install several OPeNDAP shared libraries.

If you already have the OPeNDAP-enabled version of NCL, then you can quickly test if you need to install any of these libraries by running ncl at the UNIX command line:

ncl

ncl 0> quit

If you get an error message that looks like this:

  ncl: error while loading shared libraries: libdap.so.4: cannot open shared
  object file: No such file or directory

then this means that you either need to install the OPeNDAP libraries, or you need to talk to your system administrator to find out where they reside. If they are already installed on your system, then you may need to setenv your LD_LIBRARY_PATH environment variable to the location of this library.

Otherwise, if you think you need to build the OPeNDAP libraries, then here's what you need to do:

Go to http://www.opendap.org/download/.
Click on "libdap" on the left-hand side, and download the appropriate binaries or source code (version 3.7.6 is the one we used). The libraries that should be included (or get built) are the "libdap.*" and "libdapclient.*" files.
Click on "libnc-dap" on the left-hand side, and download the appropriate binaries or source code (version 3.7.0 is the one we used). The libraries that should be included (or get built) are the "libnc-dap.*" and "libdapclient.*" files.
Note that other libraries may be needed if they are not already installed on your system. These libraries are libxml2, libcurl, SSL, and pthreads. The "libdap" link above should contain information about these libraries.

There are a few options when configuring the builds for the above software packages, so be sure to look at the "INSTALL" file in the source distribution. It is best to use as many of the defaults as possible, and to go ahead and build both shared (lib*.so) and static (lib*.a) versions of the libraries. You need the shared libraries for use with NCL.