php中如何从另一个php中调用ID获取mysql表中的行

比如说
<?php
$link = mysql_connect("localhost","root","123456");
mysql_query("use wiki");
$result = mysql_query("select * from user",$link);
echo "<form method=post>";
echo "<table border=1>\n";
echo "<tr>\n";
while ($field = mysql_fetch_field($result)) {
echo "<td>".$field->name."</td>\n";
}
echo "</tr>\n";
$num_rows = mysql_num_rows($result);
for ($i=0; $i < $num_rows; $i++){
list($id,$username,$password) = mysql_fetch_row($result);
echo "<tr>";
echo "<td name=id id=id>".$id."</td>";
echo "<td>".$username."</td>";
echo "<td>".$password."</td>";
echo "<td><a href=change.php>".修改."</a></td>";
echo "<td><a href=del.php>".删除."</a></td>";
echo "</tr>\n";
}
echo "</table>\n";
echo "</form>";
echo "<form action=add.php>\n";
echo "<input type=button value=".增加.">";
echo "</form>\n";
mysql_free_result($result);
mysql_close($link);
?>
在另外的php中，我该如何实时的获取$id？

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