memory map: M (offset, length)
	0,256	  tokenization flags
	256,128	  keyword length offset map
	384,640	  keyword strings (453 chars)
	1024,32	  option bit map
	1056,32   getopt string
	1088,256  trigraph map

freecode: trinary, alphabet  0 { 1 } 2 ;
	using three trits, the alphabet A-Z with a space/null can be encoded:
		0 space/null, 1 A, 2 B, 3 C, ...
	although this encoding is not the only one
	code is free-form, space agnostic (one or more spaces are required for it to be 'free')
	decoding is context dependent, typically using 3 or more trits
	the program comments use b(3) and the alphabet encoding above,
	but they are not cleanly split on 3-trit boundaries(!)

i A		cw
  B
i C		cc
  D
i E		cx
p F[]		keywords, token init, options init, option string, trigraph init
  G
i H		comment history
i I		ci
  J
i K		ck
i L		cl
c M[2053]	memory: token flags, keyword table, option table, trigraph table
  N
p O		start of whitespace
  P
  Q
i R		ts
  S
i T		tk
d U		defined usage message (-DU="\"help text\"")
  V
d W		defined reserved word string (-DW=\"keywords\")
  X
  Y
i Z		256
i a		global
i b(i)		decode freecode using i bits
i c		global
i d(s,i)	is a keyword?
p e		end of buffer
v f(i,i)	compat
v g(i,i)	compat_words
i h(s,i)	print i chars of s, or until null
p i		buffer
i j()		lexer
  k
i l		10 / newline
i m(c)		want(c), handles escapes
  n		global
i o		global
  p
p q		keyword index table
i r(i,i)	print arg1 as int to stdout/err by arg2, trailed by space/newline
  s		start of token
  t
  u
i v		cmd line flags
  w
  x
  y
p z		current pointer

functions

i h(s,i)	print i chars of s, or until null
i r(i,i)	print arg1 as int to stdout/err by arg2, trailed by space/newline
i m(c)		want(c), handles escapes
i d(s,i)	is a keyword?
i j()		lexer
v g(i,i)	compat_words
v f(i,i)	compat
i b(i)		decode freecode using i bits
i main(c,pp)	init, options, read, count, print