Installation Instructions

Requirements

In order to build the Nexus C API the following software has to be installed on the build system

• C compiler
• CMake >= 2.8.8
• HDF5 libraries and header files
• Optional: HDF4 libraries and header files
• Optional: MXML libraries and header files
• doxygen: for building the API documentation

Building the code on Linux

Enabling a physical file formats

By default the NAPI is only built with HDF5 support. You can explicit switch on a particular file format by defining the appropriate CMake variable during configuration

• -DENABLE_HDF5=1 for HDF5
• -DENABLE_HDF4=1 for HDF4
• and -DENABLE_MXML=1 for MXML

CMake tries then to figure out the locations of the required library binaries and header files. This should work if the library provides a pkg-config file and/or is installed in one of the systems default locations.

If your library is not in a default location you have basically two options.

1. if the library is installed with a pkg-config file you can add the path to this file to your PKG_CONFIG_PATH environment variable.
2. define CMake variables during configuration that point to the appropriate location.

For the second option the following CMake variables are available

CMake variable	Content
HDF5_INCLUDE_DIRS	location of HDF5 header files
HDF5_LIBRARY_DIRS	location of HDF5 runtime libraries
HDF4_INCLUDE_DIRS	location of the HDF4 header files
HDF4_LIBRARY_DIRS	location of the HDF4 runtime libraries
MXML_INCLUDE_DIRS	location of the MXML header files
MXML_LIBRARY_DIRS	location of the MXML runtime libraries

Enable language bindings

The library provides bindings for C++, Fortran 77, and Fortran 90. To enable them set the following variables to one during code configuration

CMAKE variable	language bindings
ENABLE_CXX	build with C++ bindings
ENABLE_FORTRAN77	build with Fortran 77 bindings
ENABLE_FORTRAN90	build with Fortran 90 bindings

Enable applications

Aside with the C-library the NAPI source distribution ships a couple of command line programs to work with NeXus files. These programs are not built by default. In order to include them in the build the ENABLE_APPS variable must be set to ON.

Program	Description
nxbrowse	browse a NeXus file
nxdir	list the contents of a NeXus file
nxconvert	convert a NeXus file to whatever?
nxtraverse nxdump nxingest nxsummary nxtranslate	no idea what this is good for

Building the distribution with these utility applications pulls in some additional build requirements. These are

• libreadline
• libtermcap
• libhistory (most probably provided by the libreadline package)
• libxml2

As one cannot select an individual program to be included in the build, all these build dependencies must be satisified when ENABLE_APPS is set to ON in order for the build to succeed.

Running the build

To build the library and program binaries simply use

$ make 

and for installation

$ make install

This procedure installs the binaries, header files, and the man pages for the programs (if configured to build them). To build the API documentation use

$ make html
$ make install-html