session_set_save_handler
session_unregister
Session Функции
PHP Manual

# session_start

(PHP 4, PHP 5)

session_start — Initialize session data

### Описание

bool session_start ( void )

session_start() creates a session or resumes the current one based on the current session id that's being passed via a request, such as GET, POST, or a cookie.

If you want to use a named session, you must call session_name() before calling session_start().

session_start() will register internal output handler for URL rewriting when trans-sid is enabled. If a user uses ob_gzhandler or like with ob_start(), the order of output handler is important for proper output. For example, user must register ob_gzhandler before session start.

### Возвращаемые значения

This function returns `TRUE` if session was started with success otherwise `FALSE`.

### Список изменений

Версия | Описание
--- | ---
5.3.0 | If session fails to start for some reason, then `FALSE` is returned where previously `TRUE` always was returned.
4.3.3 | As of now, calling session_start() while the session has already been started will result in an error of level `E_NOTICE`. Also, the second session start will simply be ignored.

### Примеры

Пример #1 A session example: page1.php

`<?php
// page1.php
session_start();
echo 'Welcome to page #1';
$_SESSION['favcolor'] = 'green';
$_SESSION['animal'] = 'cat';
$_SESSION['time'] = time();
// Works if session cookie was accepted
echo '<br /><a href="page2.php">page 2</a>';
// Or maybe pass along the session id, if needed
echo '<br /><a href="page2.php?' . SID . '">page 2</a>';
?>`

After viewing page1.php, the second page page2.php will magically contain the session data. Read the session reference for information on propagating session ids as it, for example, explains what the constant `SID` is all about.

Пример #2 A session example: page2.php

`<?php
// page2.php
session_start();
echo 'Welcome to page #2<br />';
echo $_SESSION['favcolor']; // green
echo $_SESSION['animal']; // cat
echo date('Y m d H:i:s', $_SESSION['time']);
// You may want to use SID here, like we did in page1.php
echo '<br /><a href="page1.php">page 1</a>';
?>`

### Примечания

> Замечание: If you are using cookie-based sessions, you must call session_start() before anything is outputted to the browser.

> Замечание: Use of zlib.output_compression is recommended rather than ob_gzhandler()

### Смотрите также

- $_SESSION
- The session.auto_start configuration directive
- session_id() - Get and/or set the current session id

session_set_save_handler
session_unregister
Session Функции
PHP Manual