exit
(PHP 4, PHP 5, PHP 7, PHP 8)
exit — ステータスコードかメッセージを返して現在のスクリプトを終了する
説明
スクリプトの実行を終了します。
シャットダウン関数
や オブジェクトのデストラクタ
は、exit() がコールされた場合にも実行されます。
ただし、finally
ブロックは実行されません。
終了コード 0
は、そのタスクでプログラムが成功したことを表します。
他の値は、実行中に何らかのエラーが発生したことを表します。
exit() は特殊な関数です。 パーサーに専用のトークンがあるため、文として使用して(つまり、括弧なしで)、 デフォルトのステータスコードでスクリプトを終了させることができます。
グローバルな exit() を無効にしたり、 名前空間つきの関数でシャドーイングすることはできません。
パラメータ
status
-
status
が文字列の場合は、 この関数は終了直前にstatus
を表示します。 PHP によって返される終了コードは0
です。status
が int の場合は、 この関数は終了直前にstatus
を表示します。注意: 終了コードは
0
から254
の範囲でなければならず、 終了コード255
は PHP によって予約されているため使用できません。警告PHP 8.4.0 より前のバージョンでは、 exit() は PHP の標準的な 型の相互変換のセマンティクスに基づいておらず、 また、
strict_types
宣言も適用されませんでした。また、resource や array を含む、int 型以外の値は string にキャストされていました。 PHP 8.4.0 以降は、通常の型の相互変換が適用され、無効な値に対しては TypeError をスローします。
戻り値
この関数は PHP スクリプトを終了するため、値を返すことはありません。
変更履歴
バージョン | 説明 |
---|---|
8.4.0 |
exit() は言語構造から正式な関数になったので、
通常の
型の相互変換
に従い、
strict_types
宣言も適用されるようになりました。また、名前付き引数や
可変関数
によって呼び出すこともできるようになりました。
|
例
例1 exit() の基本的な使用例
<?php
// exit program normally
exit();
exit(0);
// exit with an error code
exit(1);
?>
例2 exit() にstringを渡す例
<?php
$filename = '/path/to/data-file';
$file = fopen($filename, 'r')
or exit("unable to open file ($filename)");
?>
例3 シャットダウン関数やデストラクタが実行される例
<?php
class Foo
{
public function __destruct()
{
echo 'Destruct: ' . __METHOD__ . '()' . PHP_EOL;
}
}
function shutdown()
{
echo 'Shutdown: ' . __FUNCTION__ . '()' . PHP_EOL;
}
$foo = new Foo();
register_shutdown_function('shutdown');
exit();
echo 'これは出力されません。';
?>
上の例の出力は以下となります。
Shutdown: shutdown() Destruct: Foo::__destruct()
例4 文としての exit()
<?php
// exit program normally with exit code 0
exit;
?>
参考
- register_shutdown_function() - シャットダウン時に実行する関数を登録する
- シャットダウン関数
- オブジェクトのデストラクタ
User Contributed Notes 14 notes
If you want to avoid calling exit() in FastCGI as per the comments below, but really, positively want to exit cleanly from nested function call or include, consider doing it the Python way:
define an exception named `SystemExit', throw it instead of calling exit() and catch it in index.php with an empty handler to finish script execution cleanly.
<?php
// file: index.php
class SystemExit extends Exception {}
try {
/* code code */
}
catch (SystemExit $e) { /* do nothing */ }
// end of file: index.php
// some deeply nested function or .php file
if (SOME_EXIT_CONDITION)
throw new SystemExit(); // instead of exit()
?>
jbezorg at gmail proposed the following:
<?php
if($_SERVER['SCRIPT_FILENAME'] == __FILE__ )
header('Location: /');
?>
After sending the `Location:' header PHP _will_ continue parsing, and all code below the header() call will still be executed. So instead use:
<?php
if($_SERVER['SCRIPT_FILENAME'] == __FILE__)
{
header('Location: /');
exit;
}
?>
A side-note for the use of exit with finally: if you exit somewhere in a try block, the finally won't be executed. Could not sound obvious: for instance in Java you never issue an exit, at least a return in your controller; in PHP instead you could find yourself exiting from a controller method (e.g. in case you issue a redirect).
Here follows the POC:
<?php
echo "testing finally wit exit\n";
try {
echo "In try, exiting\n";
exit;
} catch(Exception $e) {
echo "catched\n";
} finally {
echo "in finally\n";
}
echo "In the end\n";
?>
This will print:
testing finally wit exit
In try, exiting
These are the standard error codes in Linux or UNIX.
1 - Catchall for general errors
2 - Misuse of shell builtins (according to Bash documentation)
126 - Command invoked cannot execute
127 - “command not found”
128 - Invalid argument to exit
128+n - Fatal error signal “n”
130 - Script terminated by Control-C
255\* - Exit status out of range
Don't use the exit() function in the auto prepend file with fastcgi (linux/bsd os).
It has the effect of leaving opened files with for result at least a nice "Too many open files ..." error.
Calling 'exit' will bypass the auto_append_file option.
On some free hosting this risks you getting removed, as they may be using for ads and analytics.
So be a bit careful if using this on the most common output branch.
Note, that using exit() will explicitly cause Roxen webserver to die, if PHP is used as Roxen SAPI module. There is no known workaround for that, except not to use exit(). CGI versions of PHP are not affected.
To rich dot lovely at klikzltd dot co dot uk:
Using a "@" before header() to suppress its error, and relying on the "headers already sent" error seems to me a very bad idea while building any serious website.
This is *not* a clean way to prevent a file from being called directly. At least this is not a secure method, as you rely on the presence of an exception sent by the parser at runtime.
I recommend using a more common way as defining a constant or assigning a variable with any value, and checking for its presence in the included script, like:
in index.php:
<?php
define ('INDEX', true);
?>
in your included file:
<?php
if (!defined('INDEX')) {
die('You cannot call this script directly !');
}
?>
BR.
Ninj
In addition to "void a t informance d o t info", here's a one-liner that requires no constant:
<?php basename($_SERVER['PHP_SELF']) == basename(__FILE__) && die('Thou shall not pass!'); ?>
Placing it at the beginning of a PHP file will prevent direct access to the script.
To redirect to / instead of dying:
<?php
if (basename($_SERVER['PHP_SELF']) == basename(__FILE__)) {
if (ob_get_contents()) ob_clean(); // ob_get_contents() even works without active output buffering
header('Location: /');
die;
}
?>
Doing the same in a one-liner:
<?php basename($_SERVER['PHP_SELF']) == basename(__FILE__) && (!ob_get_contents() || ob_clean()) && header('Location: /') && die; ?>
A note to security: Even though $_SERVER['PHP_SELF'] comes from the user, it's safe to assume its validity, as the "manipulation" takes place _before_ the actual file execution, meaning that the string _must_ have been valid enough to execute the file. Also, basename() is binary safe, so you can safely rely on this function.
Beware if you enabled uopz extension, it disables exit / die() by default. They are just "skipped".
https://www.php.net/manual/en/function.uopz-allow-exit.php
When using php-fpm, fastcgi_finish_request() should be used instead of register_shutdown_function() and exit()
For example, under nginx and php-fpm 5.3+, this will make browsers wait 10 seconds to show output:
<?php
echo "You have to wait 10 seconds to see this.<br>";
register_shutdown_function('shutdown');
exit;
function shutdown(){
sleep(10);
echo "Because exit() doesn't terminate php-fpm calls immediately.<br>";
}
?>
This doesn't:
<?php
echo "You can see this from the browser immediately.<br>";
fastcgi_finish_request();
sleep(10);
echo "You can't see this form the browser.";
?>
If you are using templates with numerous includes then exit() will end you script and your template will not complete (no </table>, </body>, </html> etc...). Rather than having complex nested conditional logic within your content, just create a "footer.php" file that closes all of your HTML and if you want to exit out of a script just include() the footer before you exit().
for example:
include ('header.php');
blah blah blah
if (!$mysql_connect) {
echo "unable to connect";
include ('footer.php');
exit;
}
blah blah blah
include ('footer.php');
Be noticed about uopz (User Operations for Zend) extension of PHP. It disables (prevents) halting of PHP scripts (both FPM and CLI) on calling `exit()` and `die()` by default just after enabling the extension. Therefore your script will continue to execute.
Details: https://www.php.net/manual/en/uopz.configuration.php#ini.uopz.exit
>> Shutdown functions and object destructors will always be executed even if exit is called.
It is false if you call exit into desctructor.
Normal exit:
<?php
class A
{
public function __destruct()
{
echo "bye A\n";
}
}
class B
{
public function __destruct()
{
echo "bye B\n";
}
}
$a = new A;
$b = new B;
exit;
// Output:
// bye B
// bye A
?>
// Exit into desctructor:
<?php
class A
{
public function __destruct()
{
echo "bye A\n";
}
}
class B
{
public function __destruct()
{
echo "bye B\n";
exit;
}
}
$a = new A;
$b = new B;
// Output:
// bye B
?>