#!/usr/bin/perl -w
use strict;

my $var = "Some random text.\n\tMore\n\tEven More.\n\r\t  And yet More.";

print "VAR is:$var\n";

print "Output of loop:\n";
foreach my $char (split//,$var)
{
   print get_printable($char);
}
print "\n";

sub get_printable
{
   my $char = shift;
   return $char if ($char =~ tr/A-Za-z0-9. //);
   return sprintf ("[hex%.2X]",ord($char));
}

__END__
Prints:
VAR is:Some random text.
	More
	Even More.

	  And yet More.
Output of loop:
Some random text.[hex0A][hex09]More[hex0A][hex09]Even More.[hex0A][hex0D][hex09]  And yet More.