set cookie to expire at the end of current day

Question

I want to set a cookie and have it expire at the end of the day

This works, but expires after 24 hours:

setcookie('route_upgrade_voted', true, time()+86400);

This does not work:

setcookie('route_upgrade_voted', true,  mktime(24,0,0) - time());

Answer 1

Cookie expiry times are an ABSOLUTE value, based on time since jan 1/1970. You're sending over a relative one: "tomorrow's time minus the current time". This translates into basically the number of seconds left between now and midnight, which is then interpreted as a date back in Jan 1/1970. You don't need to subtract time() at all:

echo date('r', mktime(24,0,0)), ' ',  date('r');
                             ^--note: no subtraction
Tue, 28 Jan 2014 00:00:00 -0600 Mon, 27 Jan 2014 13:30:33 -0600

And poof, you have "tomorrow at midnight", v.s. today's current date/time. So:

setcookie(..., mktime(24,0,0));

Answer 2

The easiest would be:

setcookie('route_upgrade_voted', true, strtotime("tomorrow"));

I hope this helps :)