(PHP 4, PHP 5)
setcookie — Send a cookie
bool setcookie ( string $name [, string $value [, int $expire = 0 [, string $path [, string $domain [, bool $secure = false [, bool $httponly = false ]]]]]] )
setcookie() defines a cookie to be sent along with the rest of the HTTP headers. Like other headers, cookies must be sent before any output from your script (this is a protocol restriction). This requires that you place calls to this function prior to any output, including <html> and <head> tags as well as any whitespace.
All the arguments except the name argument are optional. You may also replace an argument with an empty string (“”) in order to skip that argument. Because the expire argument is integer, it cannot be skipped with an empty string, use a zero (0) instead.
The name of the cookie.
The value of the cookie. This value is stored on the clients computer; do not store sensitive information. Assuming the name is ‘cookiename’, this value is retrieved through $_COOKIE[‘cookiename’] expire
The time the cookie expires. This is a Unix timestamp so is in number of seconds since the epoch. In other words, you’ll most likely set this with the time() function plus the number of seconds before you want it to expire. Or you might use mktime(). time()+60*60*24*30 will set the cookie to expire in 30 days. If set to 0, or omitted, the cookie will expire at the end of the session (when the browser closes).
You may notice the expire parameter takes on a Unix timestamp, as opposed to the date format Wdy, DD-Mon-YYYY HH:MM:SS GMT, this is because PHP does this conversion internally.
The path on the server in which the cookie will be available on. If set to ‘/’, the cookie will be available within the entire domain. If set to ‘/foo/’, the cookie will only be available within the /foo/ directory and all sub-directories such as /foo/bar/ of domain. The default value is the current directory that the cookie is being set in.
The domain that the cookie is available to. Setting the domain to ‘www.example.com’ will make the cookie available in the www subdomain and higher subdomains. Cookies available to a lower domain, such as ‘example.com’ will be available to higher subdomains, such as ‘www.example.com’. Older browsers still implementing the deprecated » RFC 2109 may require a leading . to match all subdomains.
Indicates that the cookie should only be transmitted over a secure HTTPS connection from the client. When set to TRUE, the cookie will only be set if a secure connection exists. On the server-side, it’s on the programmer to send this kind of cookie only on secure connection (e.g. with respect to $_SERVER[“HTTPS”]).
If output exists prior to calling this function, setcookie() will fail and return FALSE. If setcookie() successfully runs, it will return TRUE. This does not indicate whether the user accepted the cookie.
Once the cookies have been set, they can be accessed on the next page load with the $_COOKIE or $HTTP_COOKIE_VARS arrays. Note, superglobals such as $_COOKIE became available in PHP 4.1.0. Cookie values also exist in $_REQUEST.