PHP5中文手册·Loads a PHP extension at runtime -- 追寻梦想＞编程乐园＞PHP 编程

说明

int dl ( string $library )

Loads the PHP extension given by the parameter library .

Use extension_loaded() to test whether a given extension is already available or not. This works on both built-in extensions and dynamically loaded ones (either through php.ini or dl()).

参数

library

This parameter is only the filename of the extension to load which also depends on your platform. For example, the sockets extension (if compiled as a shared module, not the default!) would be called sockets.so on Unix platforms whereas it is called php_sockets.dll on the Windows platform.

The directory where the extension is loaded from depends on your platform:

Windows - If not explicitly set in the php.ini, the extension is loaded from c:\php4\extensions\ by default.

Unix - If not explicitly set in the php.ini, the default extension directory depends on

whether PHP has been built with --enable-debug or not
whether PHP has been built with (experimental) ZTS (Zend Thread Safety) support or not
the current internal ZEND_MODULE_API_NO (Zend internal module API number, which is basically the date on which a major module API change happened, e.g. 20010901)

Taking into account the above, the directory then defaults to <install-dir>/lib/php/extensions/ <debug-or-not>-<zts-or-not>-ZEND_MODULE_API_NO, e.g. /usr/local/php/lib/php/extensions/debug-non-zts-20010901 or /usr/local/php/lib/php/extensions/no-debug-zts-20010901.

返回值

如果成功则返回 TRUE，失败则返回 FALSE。 If the functionality of loading modules is not available (see Note) or has been disabled (either by turning it off enable_dl or by enabling 安全模式 in php.ini) an E_ERROR is emitted and execution is stopped. If dl() fails because the specified library couldn't be loaded, in addition to FALSE an E_WARNING message is emitted.

范例

Example#1 dl() examples


<?php
// Example loading an extension based on OS
if (!extension_loaded('sqlite')) {
    if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
        dl('php_sqlite.dll');
    } else {
        dl('sqlite.so');
    }
}

// Or, the PHP_SHLIB_SUFFIX constant is available as of PHP 4.3.0
if (!extension_loaded('sqlite')) {
    $prefix = (PHP_SHLIB_SUFFIX === 'dll') ? 'php_' : '';
    dl($prefix . 'sqlite.' . PHP_SHLIB_SUFFIX);
}
?>

注释

Note: dl() is not supported in multithreaded Web servers. Use the extensions statement in your php.ini when operating under such an environment. However, the CGI and CLI build are not affected !

Note: As of PHP 5, the dl() function is deprecated in every SAPI except CLI. Use Extension Loading Directives method instead.

Note: Since PHP 6 this function is disabled in all SAPIs, except CLI, CGI and embed.

Note: dl() is case sensitive on Unix platforms.

Note: 本函数在安全模式下被禁用。


	PHP5中文手册 assert extension_loaded PHP Options/Info PHP Manual dl (PHP 4, PHP 5) dl — Loads a PHP extension at runtime 说明 int dl ( string `$library` ) Loads the PHP extension given by the parameter `library` . Use extension_loaded() to test whether a given extension is already available or not. This works on both built-in extensions and dynamically loaded ones (either through `php.ini` or dl()). 参数 `library` This parameter is only the filename of the extension to load which also depends on your platform. For example, the sockets extension (if compiled as a shared module, not the default!) would be called `sockets.so` on Unix platforms whereas it is called `php_sockets.dll` on the Windows platform. The directory where the extension is loaded from depends on your platform: Windows - If not explicitly set in the `php.ini`, the extension is loaded from `c:\php4\extensions\` by default. Unix - If not explicitly set in the `php.ini`, the default extension directory depends on whether PHP has been built with --enable-debug or not whether PHP has been built with (experimental) ZTS (Zend Thread Safety) support or not the current internal ZEND_MODULE_API_NO (Zend internal module API number, which is basically the date on which a major module API change happened, e.g. 20010901) Taking into account the above, the directory then defaults to <install-dir>/lib/php/extensions/ <debug-or-not>-<zts-or-not>-ZEND_MODULE_API_NO, e.g. `/usr/local/php/lib/php/extensions/debug-non-zts-20010901` or `/usr/local/php/lib/php/extensions/no-debug-zts-20010901`. 返回值如果成功则返回 `TRUE`，失败则返回 `FALSE`。 If the functionality of loading modules is not available (see Note) or has been disabled (either by turning it off enable_dl or by enabling 安全模式 in `php.ini`) an `E_ERROR` is emitted and execution is stopped. If dl() fails because the specified library couldn't be loaded, in addition to `FALSE` an `E_WARNING` message is emitted. 范例 Example#1 dl() examples <?php // Example loading an extension based on OS if (!extension_loaded('sqlite')) { if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') { dl('php_sqlite.dll'); } else { dl('sqlite.so'); } } // Or, the PHP_SHLIB_SUFFIX constant is available as of PHP 4.3.0 if (!extension_loaded('sqlite')) { $prefix = (PHP_SHLIB_SUFFIX === 'dll') ? 'php_' : ''; dl($prefix . 'sqlite.' . PHP_SHLIB_SUFFIX); } ?> 注释 Note: dl() is not supported in multithreaded Web servers. Use the extensions statement in your `php.ini` when operating under such an environment. However, the CGI and CLI build are not affected ! Note: As of PHP 5, the dl() function is deprecated in every SAPI except CLI. Use Extension Loading Directives method instead. Note: Since PHP 6 this function is disabled in all SAPIs, except CLI, CGI and embed. Note: dl() is case sensitive on Unix platforms. Note: 本函数在安全模式下被禁用。参见 Extension Loading Directives extension_loaded() assert extension_loaded PHP Options/Info PHP Manual

dl

说明

参数

返回值

范例

注释

参见