Re: lack an adequate understanding of (at least) the seek function

While i do appreciate wanting to learn the intricacies of a particular tool, in this case i'd just get a different tool. Tie::File

use strict;
use warnings;
use Tie::File;

tie my @file, 'Tie::File', 'messageTest.txt' or die "can't open\n";

my $MAX = 5;

if (@file > $MAX) {
    @file = @file[0 .. $MAX - 1];
    unshift @file, "new line";
}
[download]

Tie::File even has built-in flocking.

Thanks to Corion for alerting me that i linked to File::Array ... oops :)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Comment on Re: lack an adequate understanding of (at least) the seek function Download Code

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Re^2: lack an adequate understanding of (at least) the seek function by o2bwise (Scribe) on May 23, 2005 at 21:11 UTC
jeffa, Thanks! Man, that is too cool! o2	[reply]
Re^2: lack an adequate understanding of (at least) the seek function by o2bwise (Scribe) on May 24, 2005 at 18:17 UTC
jeffa, This is REAL quick (and I am quite a beginner with OO Perl). I am wondering if the "complaint" I got for my code (which gave me the desired results) is benign. Here's the code: `#!/usr/bin/perl -w use strict; use warnings; use Tie::File; my $MAXSAVE = 5; my $name = "Duane Wade"; my $subject = "My Career"; my $message = "No one ever thought I'd be this good."; my $myTieObject = tie my @messagesIn, 'Tie::File', 'messageTest2.txt' +or die "can't open\n"; $myTieObject->flock; unshift @messagesIn, "$name\|$subject\|$message"; if (@messagesIn > $MAXSAVE) { @messagesIn = @messagesIn[0 .. $MAXSAVE - 1]; } untie @messagesIn; 1;` [download] And here's the complaint: untie attempted while 1 inner references still exist at ./messageTest2.pl line 21 <FH> line 16. Line 21 is the untie line and Line 16 is the if statement. Other than that, I am all set and much obliged! Tony	[reply] [d/l]
Re^3: lack an adequate understanding of (at least) the seek function by jeffa (Bishop) on May 24, 2005 at 18:23 UTC
You are quite welcome o2bwise. The problem is that you are `untie`'ing the wrong thingy. Try this instead: `untie $myTieObject;` [download] And there is no need to have `1;` as the last line of a script. That's only necessary for modules. Cheers! :) jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l]
Re^4: lack an adequate understanding of (at least) the seek function by o2bwise (Scribe) on May 24, 2005 at 23:38 UTC
Thanks, jeffa. I guess I was fooled by the tie being applied to the array coupled by the following in: http://search.cpan.org/~mjd/Tie-File-0.96/lib/Tie/File.pm#flock "The best way to unlock a file is to discard the object and untie the array." Man, I want to become a solid perl programmer. I was an engineer for several years in semiconductors and have been in software for ~6 years. I scripted (read: SCRIPTED) in perl for five of those. Say, I listened to the song you have posted. Not bad, but the title is much better, i.e. "the triplet paradiddle with a high-hat" - how can you beat that? If you like it, perhaps you might give a song called Serengetti (Grateful Dead off Shakedown Street) a try. All percussion where it gradually adds more and then removes it. Well, thanks again, jeffa... Cheers! o2	[reply]