Subj : sweep
To   : Eddy Thilleman
From : Jonathan de Boyne Pollard
Date : Wed Apr 04 2001 04:44 am

 ET> I also need to write software [...] to unpack any archive file 
 ET> (automatically detecting if a file is an archive at all, and if 
 ET> then which archive), [...]

Actually, I wrote something similar to this many years ago, but didn't publish 
it as part of the CLU:

    [C:\]unqwk
    Incorrect number of arguments.

    UNQWK V1.00 Unpack QWK archives using PKUNZIP style arguments.
    Copyright (c) 1993 Jonathan de Boyne Pollard      General Public Licence 
v1.00.

    UNQWK [Archiver options ...]

    UNQWK uses the first non-option argument as the archive name.

    Where the options are ('+' means currently enabled) :
     /c- Extract to console.                 /t- Test archive integrity.
     /d- Extract using full pathnames.       /f- Extract newer files.
     /n- Extract new and newer files.        /o- Overwrite existing files.
     /v- View contents of the archive.       /s  Unscramble with password.
     /p  Extract to printer.
     /j  Apply attribute mask.

    [C:\]

Later, for MishMugs, I wrote a REXX script to unpack ARCmail.  It which was 
easier to maintain and to update for new archive types.  And because unlike the 
above it was single-purpose ("Unpack files matching wildcard A from archive B 
into directory C."), I didn't have to worry about option processing, which is 
tricky to do in REXX.

 ¯ JdeBP ®

.... Dulcula, dulcula, dulcula, amorem in ventre habeo.
--- FleetStreet 1.22 NR
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