# assuming DATA pipe opened for reading...

# declare
my $current;

# begin local code block
{
  # locally define $/
  local $/ = undef;

  # slurp
  $current = <DATA>;

# end local code block
}

##</code><code>##

# open
open (DATA,"/path/to/webpage.htm") || die "Can't open page - $!";

# slurp
$current = join '', (<DATA>);

# close
close(DATA);

# match
$current =~ /<!---CURCON-->\n(.*?)\n<!---CURCON-->s;

# store
my $match = $1;