There are a few bad things going on. First, change the name of the sub to something else; "menu" is used by one of the other modules, and there is a name collision.

Second, $address doesn't get initialized anywhere. Third, don't print from the sub, return the value.

Last, the uri_escape interpolation seems to be wrong somehow, but I didn't try to rewrite it as is, because it's hard to read, and you're doing it three times needlessly. Instead, call it outside of the qq statement. Try something like this:

Main script:

#!/usr/bin/perl -w

use strict;
use CGI qw(:standard);
use URI::Escape;


require "call_b.pl";

my $go_menu = &menu2;
print "Content-type: text/html\n\n";
print $go_menu;
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call_b.pl

#!/usr/bin/perl -w

use strict;
use CGI qw(:standard);
use URI::Escape;

my $address = uri_escape("some address");

sub menu2 {
return qq|
    <td>
      <ul>
        <li><a href="home.pl?contatc=$address&amp;selected_tab=a" targ
+et="_top">home<b></b></a></li>
        <li>etc..</li>
      </ul>
    </td>
|;

}
1;
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