The simplest way is to redefine what is considered to be a line. That is done by setting $/ to the delimiter text. 

my @errors;
{
    local $/ = "=================================\n";
    open my $fh, '<', '/path/to/file.txt' or die $!;
    while (<$fh>) {
        chomp;
        push @errors, $_ if /D : Error Occurred/;
    }
    close $fh or die $!;
}

[download]
You can look up the A and B values with a regex on the raw text in @errors, or else break that into a hash with A..D as keys.

After Compline,
Zaxo

In reply to Re: Get specified number of previous line text when encountered a text match in a file by Zaxo
in thread Get specified number of previous line text when encountered a text match in a file by tariqahsan

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