PHP 5.6.16 is available


(PHP 4, PHP 5)

session_nameObtém e/ou define o nome da sessão atual


string session_name ([ string $name ] )

session_name() retorna o nome da sessão atual. Se name está especificado, o nome da sessão atual é mudado para esse valor.

O nome da sessão refere-se à id de sessão em cookies e URLs. Ela poderia conter apenas caracteres alfanuméricos; ela poderia ser curta e descritiva (i.e. para usuários com avisos em cookie habilitados). O nome da sessão é retomado para o valor padrão guardado em no pedido na hora de inicialização. Dessa forma, você precisa chamar session_name() para cada requerimento (e antes de session_start() ou session_register() serem chamadas).


O nome da sessão não pode consistir apenas de digitos, ao menos uma letra deve estar presente. Se não, um novo id de sessão é gerado a cada vez.

Exemplo #1 Exemplos session_name()


// defina o nome da sessão para WebsiteID

$previous_name session_name("WebsiteID");

"O nome da sessão anterior era $previous_name<br />";

Veja também a diretiva de configurção

add a note add a note

User Contributed Notes 6 notes

Hongliang Qiang
11 years ago
This may sound no-brainer: the session_name() function will have no essential effect if you set session.auto_start to "true" in php.ini . And the obvious explanation is the session already started thus cannot be altered before the session_name() function--wherever it is in the script--is executed, same reason session_name needs to be called before session_start() as documented.

I know it is really not a big deal. But I had a quite hard time before figuring this out, and hope it might be helpful to someone like me.
php at wiz dot cx
7 years ago
if you try to name a php session "" it gets converted to "example_com" and everything breaks.

don't use a period in your session name.
relsqui at chiliahedron dot com
6 years ago
Remember, kids--you MUST use session_name() first if you want to use session_set_cookie_params() to, say, change the session timeout. Otherwise it won't work, won't give any error, and nothing in the documentation (that I've seen, anyway) will explain why.

Thanks to brandan of who left a note under session_set_cookie_params() explaining this or I'd probably still be throwing my hands up about it.
Joseph Dalrymple
4 years ago
For those wondering, this function is expensive!

On a script that was executing in a consistent 0.0025 seconds, just the use of session_name("foo") shot my execution time up to ~0.09s. By simply sacrificing session_name("foo"), I sped my script up by roughly 0.09 seconds.
Victor H
2 months ago
As  Joseph Dalrymple said, adding session_name do slow down a little bit the execution time.
But, what i've observed is that it decreased the fluctuation between requests.
Requests on my script fluctuated between 0,045 and 0,022 seconds. With session_name("myapp"), it goes to 0,050 and 0,045. Not a big deal, but that's a point to note.

For those with problems setting the name, when session.auto_start is set to 1, you need to set the on php.ini!
slave at codegrunt dot com
10 years ago
One gotcha I have noticed with session_name is that it will trigger a WARNING level error if the cookie or GET/POST variable value has something other than alphanumeric characters in it.  If your site displays warnings and uses PHP sessions this may be a way to enumerate at least some of your scripts:

Warning: session_start(): The session id contains invalid characters, valid characters are only a-z, A-Z and 0-9 in /some/path/foo.php on line 666

I did not see anything in the docs suggesting that one had to sanitize the PHP session ID values before opening the session but that appears to be the case.

Unfortunately session_name() always returns true so you have to actually get to the point of assigning variables values before you know whether you have been passed bad session data (as far as I can see).  After the error has been generated in other words.

To Top