Hi

I'm sent data files that have CRC32Q validation on each line. I wrote a script to check each line and it used to give the same value as the checksum in the file but now it doesn't and the code hasn't been changed. Checking the data online shows that the CRC in the file is correct so it's clearly my code that's wrong, but where? In this snippet I've created a page to check that the basic code is correct for just one line. The checksum should be 0x19F112C6 but I'm getting 0x1D094D45. Many thanks. 


#!/usr/bin/perl -w

use CGI ':standard';
use CGI::Carp qw(fatalsToBrowser);
use Digest::CRC;
use strict;

my $dataToCheck = 'EGCJOBSTHANGAR534712.29N0011243.02W65.26214.10N4520
+18.84432555.4217.0255.84100503/03/2015';
my $crcOnFile = '19F112C6';
 
my $ctx = Digest::CRC -> new( width => 32, poly => 0x814141AB, refin =
+> 0, refout => 0, xorout => 0, init => 0 );

# Convert $dataToCheck to hex.
$dataToCheck =~ s/(.)/sprintf("%X",ord($1))/eg;

$ctx -> add( $dataToCheck );
my $crc = uc( $ctx -> hexdigest );
 
print "Content-type: text/html \n\n";
print '<html><body>';
 
print "Calculated value = $crc, correct value = $crcOnFile";
 
print '</body></html>';

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In reply to Digest::CRC giving unexpected result by NickGribble

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