### Update the main threads file
tie @threads, 'Tie::File', $main_threads_file or syslog('err', "update_threads couldn't open file: $main_threads_file");

if ($thread == $msg_id) {
	# put it right at the top, it's a new thread
	unshift @threads, $link;
} else {
	for my $i (0 .. $#threads) {
		if ($threads[$i] =~ $parent) {
			if ($threads[$i+1] eq "<ul type=\"disc\">") {
				# insert $link after the next element (after the <ul>)
				$threads[$i+1] .= "\n$link";
			}
			else {
				# insert three new lines/records after the parent
				$threads[$i] .= "\n<ul type=\"disc\">\n$link\n</ul>\n";
			}
			last;
				
		}
	}
	
}
untie @threads;