This function can be used in eval() -- it will halt the eval, but not the script eval"() was called in.
__halt_compiler
(PHP 5 >= 5.1.0, PHP 7, PHP 8)
__halt_compiler — Останавливает работу компилятора
Описание
__halt_compiler(): void
Останавливает работу компилятора. Эта функция может быть полезна при внедрении данных в PHP-скрипты, например, в файлы установки.
Начальная позиция данных в байтах может быть определена константой
__COMPILER_HALT_OFFSET__, которая может быть
определена, только если в файле имеется функция
__halt_compiler().
Список параметров
У этой функции нет параметров.
Возвращаемые значения
Функция не возвращает значения после выполнения.
Примеры
Пример #1 Пример использования __halt_compiler()
<?php
// открыть указанный файл
$fp = fopen(__FILE__, 'r');
// искать в указателе файла данные
fseek($fp, __COMPILER_HALT_OFFSET__);
// и вывести их
var_dump(stream_get_contents($fp));
// останавливает работу скрипта
__halt_compiler(); the installation data (eg. tar, gz, PHP, etc.)Примечания
Замечание:
Функция __halt_compiler() может быть использована только извне.
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User Contributed Notes 7 notes
-T- ¶
11 years ago
ravenswd at gmail dot com ¶
8 years ago
If "__halt_compiler();" appears in a file which is "include"d or "require"d, then the called-in file will be treated as if it physically cuts off at the "__halt_compiler();". In other words, "__halt_compiler();" only affects the physical file it's in, an outer file that pulls it in will continue to execute.
ravenswd at gmail dot com ¶
14 years ago
__halt_compiler is also useful for debugging. If you need to temporarily make a change that will introduce an error later on, use __halt_compiler to prevent syntax errors. For example:
<?php
if ( $something ):
print 'something';
endif; // endif placed here for debugging purposes
__halt_compiler();
endif; // original location of endif -- would produce syntax error if __halt_compiler was not there
?>
joey at gimo dot co dot uk ¶
10 years ago
I don't exactly know what PHP is doing internally but I don't understand the sanity behind how in token_get_all __halt_compiler is handled.
This is actually valid there:
__halt_compiler/**/ /**/ /**/ /**/ /** */();raw
Normally it pops off just any three tokens so you can have even __halt_compiler***, __halt_compiler))), etc in token _get all.
The weird thing is that is also skips T_OPEN_TAG but in the context __halt_compiler runs in this tag should not be posible. Instead it will pick up < and ? as operators and php as a T_STRING.
It ignores the token at any point so this is also valid:
__halt_compiler()/**/ /**/ /**/ /**/ /** */;raw
When I test this with a php file rather than the tokeniser it works the same.
I can only conclude that PHP/__halt_compiler is pretty weird.
I think this is from attempting to weakly imitate the same syntax handling as in functions (I guess you can put comments/whitespace anywhere). I find it annoying and counter productive though.
Even this is valid:
__halt_compiler// comment\n();raw
A general problem that compound matters is that tokenise wont check whether or not syntax is valid (tokens against each other). When running as PHP you must have ();.
Krzysiek ¶
10 years ago
Joey, you're wrong saying that __halt_compiler have strange behavior. This structure works exactly the same as any other build in structure like empty or isset (even similarly to functions; at least in tokenizer level).
About T_OPEN_TAG - after one open tag is present you didn't expect other one in current php code section, so tokenizer try to handle this "thing" in other way and it's perfectly normal...
alex at 1stleg dot com ¶
4 years ago
Please note that __HALT_COMPILER() must be uppercase if used from a pharstub: https://www.php.net/manual/en/phar.fileformat.stub.php
cwk32 at mail dot ustc dot edu dot cn ¶
9 years ago
if you find the value of __COMPILER_HALT_OFFSET__ is highly strange. Maybe...
there are some complier optimization tools, like eAccelator(very old). When the program is pre-complied and cached, the __COMPILER_HALT_OFFSET__ will be 0 = =
