Example 1. Reading File and Data Annotations

This example illustrates the use of ANfileinfo/affileinfo to get the number of
data and file annotations in the file, ANselect/afselect to get an annotation,
ANannlen/afannlen to get the length of the annotation, and ANreadann/afreadann
to read the contents of the annotation.

In this example, the program reads some of the annotations created
in the file "General_HDFobjects.hdf" by Example 1.  The program first
gets the information on the annotations in the file so that the number
of existing annotations of each kind is available prior to reading.  The
program then gets the length of each annotation and allocates sufficient
space for the contents of the annotation to be read.
For the simplicity of this example, only the data labels are read.
Any other annotations can be read by adding the for loop with
appropriate values as noted below.

This example uses the ANfileinfo/affileinfo routine to get annotation
information. This rouitne is described in the Section 10.6.1