Access to the NuGraf rendering library is made through the NuGraf
'C' Interface. This is a carefully defined set of 'C' language function calls and
parameters that allow data to be passed into or inquired from the NuGraf hierarchical
database. The 'C' language was chosen as the implementation language of choice due to its
wide acceptance, conformity across all platforms and maturity.
Unlike other similar interfaces, the NuGraf 'C' Interface is implemented using
only a handful of function calls. The core functions accept commands, data and options
using free-form, variable-length parameter lists. The power and generality of the
interface comes from the use of this free-form input since an application only has to
specify the options that it would like to change or inquire about; all unspecified
parameters are either set to predefined default values or those previously set by the
application. Furthermore, new additions or changes to the interface can be easily
accommodated without requiring the addition of new function calls or changes to the
structure of existing NuGraf applications.
3.1 Introduction