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From: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Newsgroups: comp.lang.perl
Subject: Re: perl tar file routines (perltar.perl)
Message-ID: <8756@jpl-devvax.JPL.NASA.GOV>
Date: 16 Jul 90 22:50:56 GMT
References: <1990Jul15.235710.14293@uvaarpa.Virginia.EDU>
Reply-To: lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall)
Organization: Jet Propulsion Laboratory, Pasadena, CA
Lines: 22

In article <1990Jul15.235710.14293@uvaarpa.Virginia.EDU> eichin@athena.mit.edu writes:
: Following is "perltar.perl", with the appropriate subroutines. (just 
: 	do 'perltar.perl'; 
: and then use them. Comments on my subroutine style are welcomed; is there a
: better way to make perl code *modular* and have rudimentary abstraction?)

Yes, consider using the "package" declaration, which lets you have a separate
namespace for your code.  It basically gives you the ability to differentiate
between public and private names.  Rudimentary, but nice.

: When writing, to write an EOF at the end of the tape, remember to do a 
: 	print pack("x8192",1);
: before you close your output. (I had trouble with print pack("x8192"); should
: I have?)

Hmm, well, maybe.  Packing nothing to get a null string is probably not the
most efficient way.  Nowadays "\0" x 8192 is probably more efficient.  But
if you do use pack that way, since the second argument is a LIST, you can
say pack("x8192",()) and pack a null list, which is more satisfactory
in some indefinite way.

Larry