file$ = @tmp$ + "bitwise.tmp"
      test$ = "Hello, world!"

      REM Write to file, 7 bits per character:
      file% = OPENOUT(file$)
      FOR i% = 1 TO LEN(test$)
        PROCwritebits(file%, ASCMID$(test$,i%), 7)
      NEXT
      PROCwritebits(file%, 0, 0)
      CLOSE #file%

      REM Read from file, 7 bits per character:
      file% = OPENIN(file$)
      REPEAT
        ch% = FNreadbits(file%, 7)
        VDU ch%
      UNTIL ch% = 0
      PRINT
      CLOSE #file%
      END

      REM Write n% bits from b% to file f% (n% = 0 to flush):
      DEF PROCwritebits(f%, b%, n%)
      PRIVATE a%, c%
      IF n% = 0 BPUT #f%,a% : a% = 0 : c% = 0
      WHILE n%
        IF c% = 8 BPUT #f%,a% : a% = 0 : c% = 0
        n% -= 1
        c% += 1
        IF b% AND 1 << n% THEN a% OR= 1 << (8 - c%)
      ENDWHILE
      ENDPROC

      REM Read n% bits from file f%:
      DEF FNreadbits(f%, n%)
      PRIVATE a%, c% : LOCAL v%
      WHILE n%
        IF c% = 0 a% = BGET#f% : c% = 8
        n% -= 1
        c% -= 1
        v% = v% << 1 OR (a% >> c%) AND 1
      ENDWHILE
      = v%