This library provides for reading and writing of generic font (GF)
bitmap files.  Only a single file may be read or written at a time.

None of the code that processes the GF commands actually explains what
the precise definition of those commands are.  For that, you should look
at the definition of the GF format in Metafont: The Program, by Don
Knuth, chapter 45.  It is also in the METAFONTware programs that convert
to or from GF format.

The header file is ../include/gf.h.  It explains the basics of how to
use the routines.  The source files in this directory do not repeat that
explanation.