Here is a list of all documented files with brief descriptions:

[detail level 123]

include
sdfio
file.h	Files by path, and the stream over a C file
header.h	Header of a file: size, scales, data type, dates and manufacturer
heights.h	Conversion between coded values and heights
layout.h	Layout of a buffer in memory
reader.h	Reader of a file, memory or a stream
sdfio.h	Reading and writing of ISO 25178-71 SDF surface data files
sizes.h	Sizes of buffers for the data area and for heights
trailer.h	Parsing of the fields of a trailer text
types.h	Status codes, enumerations, constants, and the structures for allocator, stream and time zone
writer.h	Writer of a file or a stream