CDF Version 2.5, VMS and OpenVMS Systems Common Data Format (CDF) is a conceptual data abstraction for storing multi-dimensional data sets. The basic component of CDF is a software programming interface that is a device independent view of the CDF data model. The application developer is insulated from the actual physical file format for reasons of conceptual simplicity, device independence, and future expandability. Version 2 of CDF has been rewritten to be portable across a wide variety of platforms. CDF files created on any given platform can be transported to any other platform on to which CDF is ported and used with any CDF tools or layered applications. A more detailed introduction to CDF can be found in the CDF User's Guide. !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! WARNING !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !! You must have a C compiler in order to build the CDF distribution. !! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! The CDF library and toolkit programs are written in C. A C compiler (ANSI standard preferred) is necessary to build the CDF distribution. The CDF distribution also contains several Fortran source files which support the Fortran interface. If a Fortran compiler is not available, contact CDF User Support for the necessary patches. Documentation for CDF consists of the CDF User's Guide, the CDF C Reference Manual, and the CDF Fortran Reference Manual. The `RELEASE.DOC' file explains how to get/print the documents. Requests for assistance or documentation should be sent to: Internet -- cdfsupport@listserv.gsfc.nasa.gov If you get the distribution, please send CDFSUPPORT a message so we can put you on our mailing list. That way you will be notified of new releases. The `CHANGES.DOC' file explains the new features of CDF V2.5. VMS/OpenVMS Installation Instructions ------------------------------------- CDF V2.5 is distributed for VMS and OpenVMS systems as a BACKUP utility save set named CDF25-DIST.BCK. To put the CDF library and tools on your system, perform the following steps. 1. Copy the CDF25-DIST.BCK file to the directory which is to be the parent directory of the CDF V2.5 distribution (library and tools) and SET DEFAULT to that directory. 2. Create (extract) the CDF V2.5 directory structure and files using the command: BACKUP/LOG CDF25-DIST.BCK/SAVE_SET/SELECT=[NCDF.CDF25-DIST...] - [.CDF25-DIST...] 3. A new directory named [.CDF25-DIST] will have been created. SET DEFAULT to that directory, the top-level CDF V2.5 directory. 4. If desired, modify the include file named `config.h' in the `[.SRC.INCLUDE]' directory to the desired default parameters for your distribution. These default parameters affect a number of actions taken by the CDF library and toolkit programs in various situations (the comments in `config.h' describe these default parameters). 5. Build the distribution with the command: MMS or @BUILD You will be prompted for exactly how you would like to build the distribution. The following prompts will be issued... If on a DEC Alpha, whether to build the distribution for a default double-precision floating-point host encoding of D_FLOAT or G_FLOAT. This determines if your host encoding (and default decoding) will be ALPHAVMSd_ENCODING or ALPHAVMSg_ENCODING. The default used by the compilers and linker on a DEC Alpha is G_FLOAT. If you choose D_FLOAT, you will have to specify additional qualifiers/parameters when compiling/linking your applications. Whether or not to build the shareable CDF library. Using the shareable CDF library can greatly reduce the size of your application executables linked to the CDF library. You may also wish to install the shareable CDF library in SYS$SHARE. Whether or not to build the Fortran test programs. These programs are used to test the Fortran interfaces to the CDF library. If a Fortran compiler is not available do not request that the Fortran test programs be built. Whether or not to build CDF's IDL interface. This interface, also known as the CDF/IDL interface, is different than the interface to the CDF library built into the IDL executable by RSI. Functionally the two interfaces are similar but syntacticly they are very different. If you want CDF's IDL interface to be built you will also be prompted for the full pathnames of the directories which contain the IDL include files (eg. EXPORT.H) and the IDL executable. If on a VAX, whether or not to use the shareable VAX C run-time library. The use of the shareable VAX C run-time library can greatly reduce the size of the CDF toolkit executables. Some informatory/warning messages from the compilers and linker may be displayed. These can be ignored and should have no effect on the operation of the library or executable programs. Several of the files being compiled are fairly large. You may need to increase your pagefile quota to avoid running out of virtual memory space. 6. Test that the library has been properly built with the command: @TEST The name of each test executed will be displayed. No other messages will be displayed unless an error occurs. 7. Install (not related to the INSTALL utility) the library and tools in the proper directories using the command: @INSTALL This will put the appropriate files in the [.LIB], [.INCLUDE], and [.EXE] directories. (They will be copied from the [.SRC...] directories.) If the shareable version of the CDF library (LIBCDF.EXE) is to be used as a true shareable image, it must be installed (using the INSTALL utility) in SYS$SHARE by a system manager having the proper privileges. The shareable version of the CDF library may also be used without being INSTALLed. 8. Delete the library(s), object files, and executables in [.SRC...] by using the command: @CLEAN This will free approximately 9500 blocks of disk space. You may also delete the entire [.SRC...] subdirectory tree if you have no further need for the source code. This will free approximately 5700 additional blocks of disk space. 9. A file named DEFINITIONS.COM exists in the top-level directory of the CDF distribution. It is a command file that a user should execute to set up the logical names and symbols necessary to use CDF. You should edit this command file for the location of the CDF distribution. A user would then execute this command file (possibly in their LOGIN.COM) to define symbols for the toolkit programs and logical names for the locations of the include files and CDF library. A logical name identifying a startup file for using IDL is also included.