Well, I have to say no and no

1. qr// works fine with \b, e.g.

   my $string = q/This is a test./;
   my $regex1 = qr(\bis);
   my $regex2 = qr(is);
   print $string =~ /$regex1/g, "\n";
   print $string =~ /$regex2/g, "\n";
   # prints
   is
   isis
   [download]

2. Your second part

   $ip = qr("192.168.3.5");

   matches e.g. "192 16833!5" but not what was being looked for. Did you maybe want to use the quotemeta function?? Then

   my $ip = "192.168.3.5";
   $ip = quotemeta $ip;
   [download]

   would be the way to go.

-- Hofmator