Nice work, astronogun! However, there were just a couple of issues...

Did you really mean my $line == "fail.txt"? You used == instead of the assignment = and it needs to be done on a file handle: my $line = <$fh>

Without having changed your code too much, try the following:

use Modern::Perl;

my $lastrow = "";

open my $fh, '<', 'fail.txt' or die $!;

while (my $line = <$fh>)
{
    $line =~ s/\n//g;
    next if !$line;
    
    if ($line ne $lastrow)
    {
        print $line, "\n\n";
        $lastrow = $line;
    }
}

close $fh;

[download]

Output:

hostname1.com

Gateway FAIL

hostname2.com

Gateway FAIL

[download]

In reply to Re^2: Delete Duplicate Entry in a text file by Kenosis
in thread Delete Duplicate Entry in a text file by astronogun

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