As Corion says, this feels like it's probably an escaping issue. It requires a few more lines, but a multi-argument piped open should escape your arguments. So: 
$dataFile = '/opt/ExportedPGPKeys/SampleData.txt';
$isEncrypted = do{
    open my $exec, '-|', qw'pgp -ea +batchmode', $dataFile, @sys or di
+e "PGP pipe failed: $!";
    binmode $exec;
    <$exec>;
};

print " The output value is $isEncrypted \n";

[download]
I say should because your perl version is very old -- Perl 5.10 fixed a host of inconsistent behaviors and I'm not certain if 5.8.4 handles system call escaping. The oldest docs I checked (5.8.8) were ambiguous on the point (link).

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: PGP encryption command not working thru Perl Backticks by kennethk
in thread PGP encryption command not working thru Perl Backticks by newperlmonkey

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