session_name

(PHP 4, PHP 5, PHP 7)

session_nameGet and/or set the current session name

Description

session_name ([ string $name ] ) : string

session_name() returns the name of the current session. If name is given, session_name() will update the session name and return the old session name.

If a new session name is supplied, session_name() modifies the HTTP cookie (and output content when session.transid is enabled). Once the HTTP cookie is sent, session_name() raises error. session_name() must be called before session_start() for the session to work properly.

The session name is reset to the default value stored in session.name at request startup time. Thus, you need to call session_name() for every request (and before session_start() is called).

Parameters

name

The session name references the name of the session, which is used in cookies and URLs (e.g. PHPSESSID). It should contain only alphanumeric characters; it should be short and descriptive (i.e. for users with enabled cookie warnings). If name is specified, the name of the current session is changed to its value.

Warning

The session name can't consist of digits only, at least one letter must be present. Otherwise a new session id is generated every time.

Return Values

Returns the name of the current session. If name is given and function updates the session name, name of the old session is returned.

Examples

Example #1 session_name() example

<?php

/* set the session name to WebsiteID */

$previous_name session_name("WebsiteID");

echo 
"The previous session name was $previous_name<br />";
?>

Changelog

Version Description
7.2.0 session_name() checks session status, previously it only checked cookie status. Therefore, older session_name() allows to call session_name() after session_start() which may crash PHP and may result in misbehaviors.

See Also