Cron job from php (at command to be exact)

Question

I want to run a script just ONCE by setting up a cron job using "at" command. I'm using this now:

<?php
include "config.php";
if (isset($_POST['add']))
{
 $sql = mysql_query("INSERT INTO {$table}(msg) VALUES('{$_POST['msg']}')");
 if ($sql)
 {
  $cmd = "wget /var/www/index.php?id=" . mysql_insert_id() . " | sudo at " . $_POST['runat'];
  exec($cmd);
  echo exec("atq");
  echo $cmd;
 }
 exit();
}

echo "<form action='{$_SERVER['PHP_SELF']}'  method='POST'>";
echo "<input type='text' name='msg' />";
echo "<input type='text' name='runat' />";
echo "<input type='submit' name='add' />";
echo "</form>";

?>

However, this doesn't seem to be working. Am I doing this right? Or could you recommend something else?

Answer 1

You are using at command in wrong way. You need to echo command and pass it to at. Try it like that:

$cmd = "echo wget /var/www/index.php?id=" . mysql_insert_id() . " | sudo at " . $_POST['runat'];