The following code will print your string to an output file with double quotes:

use warnings;
use strict;
my @head = '<reportparameters name="hostname">localhost</reportparamet
+ers>';
open my $OUT_FH, '>', 'out.txt' or die "can not open out.txt: $!\n";
print $OUT_FH  "@head\n";
close $OUT_FH;
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This is the contents of the output file "out.txt":

<reportparameters name="hostname">localhost</reportparameters>
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I'm not sure what you are trying to accomplish with the perl one-liner. Can you elaborate?