TUG PDS CERT 1.01 (Documentation)

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                       F i l e    I n f o r m a t i o n

* DESCRIPTION
Text file for DEARC.PAS.

* ASSOCIATED FILES
DEARC.PAS
DEARCABT.PAS
DEARCGLB.PAS
DEARCIO.PAS
DEARCLZW.PAS
DEARCUNP.PAS
DEARCUSQ.PAS
DEARC.TXT

* CHECKED BY
DRM - 08/08/88

* KEYWORDS
TURBO PASCAL V4.0 DOCUMENTATION

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}


          A while back, I stumbled across a file called DEARC512.ARC on a
          bbs that I happen to frequent.  Contained in this archive was a
          Turbo Pascal program for extracting files from an ARChive.  While
          not as fast as the more familiar ARC, ARCE, and PKXARC programs,
          the source code provided me with the insights into ARC file
          structure and decompression algorithms that I had been looking
          for (I've always been a bit curious about things of this type). I
          found something lacking in the source code, however, and that was
          support for "squashed" files (as created by Phil Katz's PKARC
          program).

          About that time, a file called NARC11.ARC was beginning to appear
          in the upload directories of many bulletin boards. This file,
          created by Gary Conway, contained a program to front-end ARC with
          a mouse driven menu. It also happened to contain the most
          understandable documentation of ARC compression methods I had
          ever encountered (thanks, Gary).  Whether you use Gary's program
          or not, it is well worth the download time just to have a peek at
          his documentation.

          With the NARC document in hand, I was able to modify the original
          program (DEARC512.PAS) to include support for extraction of
          "squashed" files.  In doing this, I wanted to avoid, as much as
          possible, changing the "flavor" of the original coding, which
          actually worked quite well.  For this reason, a comparison of
          dearcsq.pas with dearc512.pas will reveal very few changes (e.g.,
          I left the original argc and argv functions in, rather than
          replace them with Turbo's ParamCount and ParamStr functions).

          My thanks to Gary Conway, the original author of dearc.pas
          (whoever you are) and also to Roy Collins and David W. Carroll
          who have also made contributions to the upkeep of this program.



                                                                rpb
                                                                7/28/87


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          my experience was similar - i ran into both dearc512 and dearcsq
          (richard's un-squashing version).  i thought it might be nice to
          modernize the code (which had been written for cp/m 86 and dos
          compatibility).  i felt relatively secure that eliminating the
          cp/m end of things wouldn't hurt anybody (after all,  there's
          always the old version).  i also added a few 'bells and
          whistles',  such as time/date stamping of extracted files to
          match the dates in the archive,  more descriptive decompression
          messages ('unCrunching', 'unSquashing',  etc),  as well as a few
          bug fixes and general tidying up of the code.  some speed is
          gained by the fact that floating point is no longer used,  along
          with a buffer size of 512 rather than 128 bytes,  more reflective
          of the DOS world.

          ditto richard's nod to gary conway's narc docs - i would also
          recommend the ARC source and,  if you can find it,  a completely
          incompatible but very good (and well-documented with source)
          ARC/UNARC utility called DWC (check the Cork Board,
          (201)-463-001).

          and of course,  hats off to richard,  roy,  david,  and the tomb
          of the unknown original author.  sorry i didn't add another ARC
          version this time - there aren't any new ones!

                                                                 paul
                                                                 7-26-88

