my $bit_in = '';
   my $r_bit;
   vec($bit_in, fileno($f), 1) = 1;
   while(1) {
      select($r_bit = $bit_in, undef, undef, tick_len);

# if select said there was data...
      if(vec($r_bit,fileno($f),1)) {
         my $in;

# connection lost if sysread returns undef
         return unless $f->sysread($in, 1);

# otherwise, it's good data
         $str .= $in;
         last if $in eq "\n";
      }
   }