Font Instance Characteristics
-----------------------------

 - Function: font-instance-properties font
     This function returns the properties (an alist or `nil') of
     FONT-INSTANCE.

 - Function: x-make-font-bold font &optional device
     Given an X font specification, this attempts to make a "bold" font.
     If it fails, it returns `nil'.

 - Function: x-make-font-unbold font &optional device
     Given an X font specification, this attempts to make a non-bold
     font.  If it fails, it returns `nil'.

 - Function: x-make-font-italic font &optional device
     Given an X font specification, this attempts to make an "italic"
     font.  If it fails, it returns `nil'.

 - Function: x-make-font-unitalic font &optional device
     Given an X font specification, this attempts to make a non-italic
     font.  If it fails, it returns `nil'.

 - Function: x-make-font-bold-italic font &optional device
     Given an X font specification, this attempts to make a
     "bold-italic" font.  If it fails, it returns `nil'.