reference

[E.Horn]

Hello!
I have a problem to get the contents of a variable!
How can i reference the contents of the $id variable?
sub get_s($da,$id)
{
 my $url='http:...db=';
 my $da=$_[0];
 my $id=$_[1];
  my $p_id='&id=';
   my $m='&ret=xml';
 return $url.$da.$par_id.$id.$m;

}
sub pro()
{
 my $xmldoc = $_[0];
 my $parser = new XML::DOM::Parser;
 my $doc = $parser->parse($xmldoc);
 my $nodes = $doc->getElementsBy("");

 for (my $i=0; $i<$nodes->getLength(); $i++)

 {my $node = $nodes->item($i);
    my $accessions=$node->getElementsBy("");
   my $id=processNode($accessions->item($i));
 my $url=& get_s("nucle",(how do i get the contents of $id at this
position?);

 my  $doc_s=get $url;
}