I opened the file in string context and was able to find the pattern successfully. But I could not substitute the matched pattern with required pattern 

$extra = "This is i will place after match\n.an this too";
open (my $fh, '+<', $file);
$data = <$fh>;
$data = s/(.*entry)\n([^\n]*)\n/$1\n$extra/

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The $1 is found successfully. But could not do the substitution in the file.

In reply to Re^2: Regex and writing lines in file by amma
in thread Regex and writing lines in file by amma

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