set and get cookie in a same session

Anon

I have a script like this:

<?
...
if ($something)
setcookie("abc", "YES", time()+3600);
else
setcookie("abc", "NO", time()+3600);
...
?>

...
...
<?
if ($HTTP_COOKIE_VARS["abc"] == "YES")
print "do something";
?>
....
....

Is my program logic wrong ? I asked because I couldn't get the cookie value at the presentation layer when it first load. It only gets the cookie value after I've reloaded the page. Can I set a cookie and get its value in a same session ? Like the above program. Please advise.
Thank you!

Anon

Please note that the Presentation Layer is in HTML code. I don't know why it wouldn't appear the tag here.

Anon

You cannot get and set the cookie in the same session, because
'setting' it (as referred to here) merely records the cookie information
to be sent to the client. Until the client requests another page,
you haven't received the cookie yet.

But you should be able to work around this: if you're still running the
same PHP script that set the cookie, couldn't you also set some
kind of global variable that says, in effect, "That cookie is
pending and here's what the value will be"?

Anon

Thanks for clearing my doubts and the suggestion. I've worked through it with global variables.
What I've done is to set the value to a variable and, I print a hidden tag in the presentation layer. So, the script can retrieve the value without having set any cookie.

Is that a reasonable solution ?

piece of code:
<?
if($something)
$abc = "YES";
else
$abd = "NO";
?>

...
<input type="hidden" name="abc" value="<? print $abc ?>">
....