[comp.sys.ibm.pc] uncompatible archives?

jvc@mirror.UUCP (04/13/87)

/* Written 12:29 pm  Apr  9, 1987 by japplega@csm9a.UUCP */
>As to PKARC, I am currently discouraging the use of PKARC to archive files
>until it is modified to use another extension.  PKARC archives are NOT
>compatible with ARC 5.12 or 5.20!!!  This is seriously complicated by the
>fact that it's files are labeled with the same extension!  ARC is an industry
>standard... PKARC is not!  PKXARC will unarc files from 5.12 and some from
>5.20 much faster than ARC... but ARC520.COM makes an ARCE.COM that works just
>as fast!!!
>
>     Joe Applegate - Colorado School of Mines Computing Center
>            {seismo, hplabs}!hao!isis!csm9a!japplega
>
>       *** Unix is a philosophy, not an operating system ***

PKARC **DOES** make archives that are 100% compatible with ARC 5.12 and
ARC 5.20 (Even if you use comments in your PKARC files, however, ARC
will not know about nor preserve these comments).  PKARC has a switch
setting which allows this compatibility (I've heard, probably from
here, that there is a patch to change the default for this switch).
Even when in 100% ARC compatible mode, PKARC is *much* faster than
ARC (There are some test results somewhere in this notes file).

I do agree that it is confusing if one uses PKARC to create an archive
with the .arc extention but in a form not be compatible with ARC.  However,
it is just as confusing and frustrating when someone uses the latest and 
greatest ARC to create an archive which is unreadable buy older versions 
of ARC.

Just changing the archive extention (maybe to .pka) will not be the
cure-all since these extentions do not indicate what version software
was used to create the archives.  Also, odds are that every time ARC 
comes up with a new technique, PKARC will copy it, and vise versa.

>As to PKARC, I am currently discouraging the use of PKARC to archive files
>until it is modified to use another extension.  PKARC archives are NOT
>compatible with ARC 5.12 or 5.20!!!  This is seriously complicated by the
>fact that it's files are labeled with the same extension!  ARC is an industry

As I said above, PKARC archives are compatible with ARC 5.12 and 5.20,
however,
I am currently discouraging the use of ARC 5.20 to archive files until it
is modified to use another extension.  ARC 5.20 archives are NOT compatible
with ARC 5.1* (or earlier versions)!!!  This is seriously complicated by the
fact that it's files are labeled with the same extension!
:-)   :-)   :-)   :-)   :-)   :-)   :-)   :-)   :-)   :-)   :-)   :-)   
:^)  

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Jim Champeaux	jvc@mirror.TMC.COM
		{mit-eddie, ihnp4, wjh12, cca, cbosgd, seismo}!mirror!jvc
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jvc@mirror.UUCP (04/14/87)

Someone sent me mail suggesting that the last paragraph of my note
titled 'uncompatible archives' (I know it's misspelled but I didn't
catch it in time to fix it) could be misinterpreted.

To clear things up:

ARC 5.20 *is* compatible with ARC 5.*.  However, PKX34A20 is also
compatible with ARC 5.* providing you use the compatibility switch.

Sorry for any confusion.