#!/usr/bin/perl -w
use strict;

my $prefix = shift or die "Usage: multiplex PATH_PREFIX\n";

my $file = "";
open OUT, "> /dev/null";
while (my $line = <>) {
  chomp $line;
  if ($line =~ /^<+\s*(\S+)\s*<+$/) {
    close OUT;
    $file = lc("$prefix$1");
    open OUT, "> $file" or die "Can't open output file '$file'\n";
  } else {
    die "No output file specified.\n" unless $file;
    print OUT "$line\n";
  }
}
close OUT;

