I am not sure exactly what your end goal is.

In Perl regex'es the \s stands for any whitespace character (space,\n,\r,\f,\t). \s* would mean zero or more of these and \s+ would mean at least one of these and possibly more of them. \s is an easy "short hand" for any of these "non-printable" space characters.

It could very well be that as other posters have suggested that the problem lies with 16 bit vs 8 bit chars. But then again, perhaps not if the issue is just "blank space" characters vs some other character.

Consider the following code. Common function names are: isprint() or isprintable() for a yes/no value. Below my sub get_printable() always returns something.

#!/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][hex
+0D][hex09]  And yet More.
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