PHP: session_set_cookie_params

User Contributed Notes
session_set_cookie_params

jordi at jcanals dot net
15-Nov-2004 07:39


Something that has taken me some time to debug: session_set_cookie_params() does not work when the domain param is just a one level domain, like it was a TLD.



I have a site in an intranet and our internal domain is .local, so trying to set the cookie session to the .local domain does not work:



session_set_cookie_params(0, '/', '.local'); // Does not work



In all test I've done, setting the domain only works for SLDs and above: 



session_set_cookie_params(0 , '/', '.sld.local'); Does work



This is nothing to do with PHP but the http protocol, witch does not permit setting cookies for TLDs for obvious security reasons.

treeml at itree dot org
13-Aug-2003 05:13


If the server time is not properly set, e.g(it is behind the client time).    Excution of the following code



session_set_cookie_params(2000);

session_start();



will NOT set/send cookie to  Internet Explorer 6.0,



even though it will set the cookie on Mozilla/Firebird browser.  But the cookie will get set without the session_set_cookie_params(); 



Same holds true for following code,



$expiry = 60*30;

session_start();

setcookie(session_name(),session_id(), time()+$expiry, "/");

 



For some reason IE is really sensitive to cookie times. It won't even accept the cookie!!

 This took me quite a while to figureout, for I thoguht it was an IE cookie security issue.

Kato
04-Jan-2003 02:54


Cookies can be set with a long notation expiry time...



Thus, you can use:



"Sat Jan  4 11:55:15 MST 2003"



This has helped me in the past to deal with the clients computer differing in time... since their browser will adjust accordingly.

mail at paul-roberts dot com
22-Dec-2002 08:08


if you want/expect the session to last as long as your cookie then also see

http://www.php.net/manual/sv/function.session-cache-expire.php

shrockc at inhsNO dot SPAMorg
18-Jun-2002 11:19


when setting the path that the cookie is valid for, always remember to have that trailing '/'.



CORRECT:

session_set_cookie_params (0, '/yourpath/');



INCORRECT:

session_set_cookie_params (0, '/yourpath');



no comment on how long it took me to realize that this was the cause of my authentication/session problems...

gavin_spam at skypaint dot com
26-Feb-2002 04:58


The first argument to session_set_cookie_params is the number of seconds in the future (based on the server's current time) that the session will expire.  So if you want your sessions to last 100 days:



$expireTime = 60*60*24*100; // 100 days

session_set_cookie_params($expireTime);



I was using time()+$expireTime, which is WRONG (a lot of the session_set_cookie_params() examples I found get this wrong, but probably don't care because they are just doing "infinite" sessions).

php at mike2k dot com
09-May-2001 04:16


[Editor's Note:





Rasmus' Solution from the PHP-General list:





Just use a session cookie (by not providing an expiry time) and add the


server's expiry timestamp to the value of the cookie.  Then when you get


that cookie sent to you, check it against your server's time and make the


decision on whether to accept the cookie or not based on that.





That way you are immune from people not having their system clocks set


right.





-Rasmus





--zak@php.net]





A couple things I noticed when using this. I think it only works if you set the session_set_cookie_params() function BEFORE the session_start() function.





Also, when you set the "lifetime" on the cookie, it takes the seconds offset from the SERVER. it sends the cookie encoded to timeout at the SERVER time. So if your server is +2 minutes ahead of the client, and you set the cookie to timeout after 30 seconds, the client actually has 2 minutes and 30 seconds before the cookie times out. I don't know if there's any way that this can be patched in future versions, and the only alternative I think is setting cookies in javascript, which is hardly the point when using all these specific session functions.

session_set_cookie_params

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