session_name
(PHP 4, PHP 5, PHP 7, PHP 8)
session_name — Get and/or set the current session name
Description
$name = null): string|false
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). Ifnameis specified and notnull, the name of the current session is changed to its value.WarningThe 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, or false on failure.
Changelog
| Version | Description |
|---|---|
| 8.0.0 |
name is nullable now.
|
| 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. |
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 />";
?>
