adv440:   The main directory, containing everything you need to build

  README.txt   Information about AdventureII (now known as Adv440)

  advII.f:     program source derived from code2t (see below), incorporating
               some Nov 2001 bug fixes and corrections by Jack Pike. This is
               an F77 code, so you need either an F77 compiler, or f2c
               and a C compiler, in order to build it. The f2c-derived
               C source is not included, because it needs f2c.h to compile
               and libf2c to link. Machines which have these, will also
               have f2c itself. Other machines would not be able to
               build the C source anyway.

  advII.dat:   "Full data base (coded to prevent reading of comments etc)"
               The data file which is accessed by advII.f at runtime.

  contents.txt This file

  bits:        A sub-directory with bits and pieces, none of which are
               required to build or play the game. It contains:

    code2c:      "Program with text packing(slow to load but needs less store)"
                 Jack Pike's original Fortran 66 program with text compression.
                 Jack's work on this led him to publish a paper on text 
                 compression:
                   "Text compression using a 4 bit coding scheme" by J. Pike,
                   The Computer Journal, vol 24, No. 4, 1981 (rec. Sep 1980)
                   
    code2t:      "Program without text packing"
                 Jack Pike original program without text compression. His
                 adventure effort indirectly inspired another published paper:
                    "A free-format data input scheme written in standard
                    FORTRAN (ANSI 66)" by G.F.Butler and J. Pike
                    The Computer Journal,, vol 24, No. 3, 1981 (rec. Oct 1979)

    advent.txt:  "Full DEC data base (uncoded data base,lower case)"
                 This is the mixed case, "human-friendly" database a part
                 of which got recovered in December 1999 from a Prime archive.
                 It needs processing into the format understood by the program.
                 Since the conversion program didn't survive (nor did a
                 memory of it, baffling Jack and myself for a while), a
                 Perl script (cv.pl) is included, which does the same task.
                 However, it should be noted, that since the I/O element
                 of the program had to be re-written anyway, the format
                 expected by advII.f is simpler than that expected by
                 either code2c or code2t. See below for details.

                 You may notice, BTW, that section 12 of the database
                 is not actually used. Jack Pike at some point removed
                 all code and text which had anything to do with 
                 restrictions on playing (in multi-user environments). 
                 However, I deliberately reinstate the section 12 text as
                 preserved in the earlier located, incomplete copy of
                 the database, simply to give some idea as to what was
                 involved.

    codbug.txt:  "Log of bugs found and improvements"
                 A list of patches as distributed by Jack Pike in 1981.
                 All the patches in question have been applied to advII.f
                 The main interest of this document lies in the fact that
                 it demonstrates two things: (a) that despite the master
                 database being written in mixed case, the program was
                 being distributed in uppercase only (which fits with the
                 messages hard-coded into code2c and code2t being in
                 upper case, and (b) that the text in the post processed
                 database was lightly scrambled to make reading more
                 difficult.      
 
    code2.txt:   "Comments for program(some out of date)"
                 The restored advII.f source restores program comments,
                 but the original code (both code2c and code2t) had
                 comments stripped off, and replaced with 'CC number'
                 comment lines. The comments, together with their 
                 'CC number' labels were kept separately in this file.
                 I believe this file was not a part of normal 
                 distribution of Adventure II, and Jack Pike sent it
                 to me separately, once we got down to fixing some
                 bugs I reported back to him.

    history.txt: The contents of a sheet of paper, hand-written by
                 Jack Pike, which outlined a (fictional) brief history
                 of the Colossal Cave, and also had some thoughts what
                 additional commands the game should understand.
 
    cv.pl:       My Perl script for dbs conversion from the human-friendly
                 format to the format expected by the program. The original
                 conversion program is lost (and its existence was
                 entirely forgotten both by Jack and by me), and our
                 understanding of its functionality is derived from
                 the mismatch between the format of the preserved database
                 and the data requirements of the preserved code, 
                 coupled with a strong indication in our past correspondence
                 that the database was maintained in a readable format,
                 and had to be converted to another format for distribution
                 (forcing upper case as a part of the conversion).

                 Note that in adapting adv440 I/O and character handling
                 I took the liberty of simplifying the structure of text
                 sections of the dbs file expected by the program. All
                 that the conversion program has to do is to force text
                 into upper case and scramble it by shuffling about
                 4-character blocks. 
                
                 In the following, all numbers are assumed to be blank
                 padded, right justified:
 
                 The structure of a line of text expected by advII.f is: 
                 a 4-digit text ID number, followed by the scrambled text.
 
                 The original format, as expect by code2t or code2c was:
                 a 4-digit text ID number, a 2 digit number of
                 4-character blocks in the text line (i.e. six character
                 altogether), followed on the next line by the scrambled
                 text.

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