Format of DOS .CPI (Code Page Information) file header:
Offset	Size	Description	)
 00h	BYTE	ID tag
		FFh FONT file (Standard for generic display or
		      printer font files used by MS-DOS, PC-DOS, DR DOS
		      and Novell DOS)
		7Fh DRFONT file (Used by DR DOS 6.0 / Novell DOS 7 for
		      enhanced & compressed display font files. DR DOS 6.0
		      and Novell DOS 7 still support the standard FONT
		      files, thus allowing leaning of .CPI files from
		      MS-DOS to DR DOS / Novell DOS!)
 01h  7 BYTEs	ID string
		"FONT	" = FONT file (Standard for display or printer)
		"DRFONT " = DRFONT file (Enhanced compressed format used
			    by DR DOS 6.0 / Novell DOS 7 for display fonts)
 08h  8 BYTEs	reserved (0)
 10h	WORD	number of pointers (1)
 12h	BYTE	type of pointers (1)
 13h	DWORD	pointer to file offset of FontInfoHeader
		(Generally pointing to the byte just after FontFileHeader,
		     that is 0000h:0017h. Due to extra data at offset 17h, this
		     value has changed with DR DOS 6.0 / Novell DOS 7 DRFONTs!
		     "MS-DOS 4.0 programmers reference" claimed word offset
		     +15h as an endmarker (0000h), but actually it is the
		     High-Word of the pointer.)
--- Extended FontFileHeader with DR DOS 6.0 / Novell DOS 7 DRFONTs: ---
 17h	BYTE	number of fonts per codepage supported by this file
		     (N=4 with both DR DOS 6.0 / Novell DOS 7 DRFONT files)
 18h  N	BYTEs	cellsize (Height) of fonts 1..N
		the cellsize corresponds with the character boxes height,
		  but is also the count of bytes used for each of the
		  characters inside the font data (as currently all fonts
		  are organized heightx8 and 8 pixel width is just one byte).
 var  N DWORDs	file offsets of DisplayFontData.