Amiga ISO Collection/AmigaUtilCD1.iso/Archiver/xlha193.lha/XLHA/XLHA.doc

Text File | 1994-11-20 | 6.8 KB | 168 lines

      8b        d8  88           88        88         db    Mat Bettinson
       Y8,    ,8P   88           88        88        d88b
        `8b  d8'    88           88        88       d8'`8b    10-Nov-94
Welcome   Y88P      88           88aaaaaaaa88      d8'  `8b
  to      d88b      88           88""""""""88     d8YaaaaY8b    2:254/205
        ,8P  Y8,    88           88        88    d8""""""""8b    39:139/5
       d8'    `8b   88           88        88   d8'        `8b
      8P        Y8  88888888888  88        88  d8'          `8b   V1.93


Good day to you fellow Amigans.

I've you've used XLHA before and know about it then bugger off and use this
version as it's pretty easy to work out:

New to Version 1.93:

Bug fixes. No internal quotes on some commands. Strange people with device
names with a space in them would cause XLHA to fail and do wierd things.

Got rid of NUKE library since the new RAKE beats it even in decompression
speed and replaced it with SQSH (Squash) library which is bloody fantastic
for samples and modules. Better than LHA!

Text tidied up. Code optimised slightly.

New to Version 1.92:

New LHA mode. The idea that started it all... IE gathering files with no
compression and LHAing afterwards. Now XLHA will recognise the file type as
being an XPK XLHA file or an 'LHA squared' file and act accordingly for
extraction. For Archiving you are given the option of LHA mode or using XPK
for all the others etc. LHA is slower than most (though not SHRINK!) but
has a VERY good compression to speed ration. If you have a registered LHA
1.50r then you'd be mad not to use that as it's VERY good. Again... If
you've a fat CPU Shrink still kicks butt.

Please note I've neglected the CLI mode this time round. CLI mode doesn't
support LHA mode as I really do have to re-write that bit anyway and I HAVE
been up for 36 hours! 8-|

Usage:

XLHA

That's right! With no commands it's ALL GUI driven. If you should WANT to
drive it from the CLI then you can with the A and E commands.

However... They may be less efficient than the GUI and don't enable you to
select files and dirs for archiving at the same time.

Basically the CLI options MAIN limitation is that it will really only do a
single directory. Bummer but how else can you do it? You can't ADD to an
XLHA file (yet).

Ok...

The XLHA FAQ:

<1> What is XLHA?

Basically I discovered (though I'm sure I'm not the first) that if you can
bundle all the files destined for an archive up FIRST and THEN hit it with
LHA it makes a MASSIVE difference.

Simply put. XLHA is an LHA archive bundled up without compession (-z switch)
and then compressed with the XPK system. The XPK system can obviously use
any one of the XPK compression libraries to decide exactly WHAT sort of
compression you want.

<2> What do I need in addition to XLHA?

Basically a full XPack distribution wouldn't hurt. As a minimum you'll need:

'reqtools.library'
'rexreqtools.library' (yes XLHA is a compiled rexx program in this version)
'xpkmaster.library' (comes with Xpack current version 2.4)

'xpk????.library' in LIBS:compressors as you will have once XPK is installed.
NUKE, RAKE, SHRI and MASH are defaults in the GUI so you should have at
least them though it wont matter until you come to USE one.

BTW The default CLI mode library is MASH at 50% which is very reasonable.
Don't use it higher as it just slows down for a couple of less bytes.

'LHA' (Any standard LHA compatible version will do but it MUSt be called LHA
and it MUSt be in your *C:* directory! Only been tested with Stephan Bobergs)

'Copy' and 'Delete' in C: (Who hasn't?)

'XPK' in C: (Comes with XPack distribution. Older one but gives CPS display)

That's it... Seems like a lot but the only bits you're likely NOT to have is
the XPK bits and they all come in one package...

The bare nuts and bolts can be freq'ed from my BBS.

Creations 2:254/524 Phone: [phone]

'XPKBARE.LHA' - Essentials plus all latest libraries.

'XPKLIBS.LHA' - Just latest XPK libraries.

'XLHA' magic filename for the latest version of XLHA.

If you've got any thoughts and/or presents I'd appreciate that whilst you're
in the freqing mood. :-) You may be able to con the Arexx source out of me!

<3> What is XLHA's limitations?

The only REAL one (and it's a biggy) is that you can't ADD to the archive
once compressed. Bummer but it's the whole reason why the files are so much
smaller than just plain LHA.

BUT the GUI enables you to select a bunch of files and dirs and will create
an .XLHA file. MUCH quicker than the Dopus buttons I posted awhile ago.

You can make your OWN .XLHA files. You CAN just continuously add files to
the LHA archive uncompressed. IE just like normal but with the -z switch...
then at the end, hit the file with XPK etc. XLHA is easier and quicker! :-)

Right... Another MAJOR thing you should be aware of is that XLHA will
require a LOT of disk space... Enough for the entire total source size in
the destination dir. At one stage the data hasn't been compressed and is
just a very large file (if a big archive obviously :-) before compression.
Also XPK creates a NEW file. It reads from the old one and writes the
compressed data to a new file then renames it to the old filename and
deletes the old one. Safe but basically you could need 1.5 times the
original source size free on the destination. When finished you'll have just
the tiny .XLHA archive... No real problem just remember not to pack ANYTHING
to RAM unless it's small. I KEEP falling for this. :-/

<4> So what's the future for XLHA?

Well... Since the files can be generated by anybody with existing
shareware/freeware/PD kit and they are SOOOOooo much smaller than LHA I
should HOPE it becomes quite popular.

I have plans for a virtual block achiver coded in ASM with it's own format
as well as supporting this .XLHA format. However... That probably some time
away... Meanwhile I find it easier to write large sexy rexx scripts to do it
as the speed is really dependant on the external archivers.

BTW watch out for Jonothan Forbes LZX. The man who wrote the best BBS
software ever is about to write the best archiver ever. Keep an eye out.

Bugs?

Don't know... I've not really checked it with everything with this version.
Let me know if you find any!


That's it...

Oh... Nasty copyright bits:

XLHA is the property of Mat Bettinson and may be freely distributed and
included on any archives and sent anywhere etc... It may NOT be sold and
this doc file must be present in the archive. XLHA is NOT PD.

Now THAT'S it!
     _ ___
/\/\(-) |  Sysop of Creations, plot hatcher and general Aussie Nuisance.

... "Easy man! I say we let 'em have it with the laser bazookas!"
    "There's a great Idea but I see a small problem with the plan.... "