(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
ini_get_all — Gets all configuration options
$extension = null, bool $details = true): array|falseReturns all the registered configuration options.
extension
       An optional extension name. If not null or the string core, the function returns only options
       specific for that extension.
      
details
       Retrieve details settings or only the current value for each setting.
       Default is true (retrieve details).
      
   Returns an associative array with directive name as the array key.
   Returns false and raises an E_WARNING level error
   if the extension doesn't exist.
  
   When details is true (default) the array will
   contain global_value (set in
   php.ini), local_value (perhaps set with
   ini_set() or .htaccess), and
   access (the access level).
  
   When details is false the value will be the
   current value of the option.
  
See the manual section for information on what access levels mean.
Note:
It's possible for a directive to have multiple access levels, which is why
accessshows the appropriate bitmask values.
Example #1 ini_get_all() examples
<?php
print_r(ini_get_all("pcre"));
print_r(ini_get_all());
?>
The above example will output something similar to:
Array
(
    [pcre.backtrack_limit] => Array
        (
            [global_value] => 100000
            [local_value] => 100000
            [access] => 7
        )
    [pcre.recursion_limit] => Array
        (
            [global_value] => 100000
            [local_value] => 100000
            [access] => 7
        )
)
Array
(
    [allow_call_time_pass_reference] => Array
        (
            [global_value] => 0
            [local_value] => 0
            [access] => 6
        )
    [allow_url_fopen] => Array
        (
            [global_value] => 1
            [local_value] => 1
            [access] => 4
        )
    ...
)
Example #2 Disabling details
<?php
print_r(ini_get_all("pcre", false)); // Added in PHP 5.3.0
print_r(ini_get_all(null, false)); // Added in PHP 5.3.0
?>
The above example will output something similar to:
Array
(
    [pcre.backtrack_limit] => 100000
    [pcre.recursion_limit] => 100000
)
Array
(
    [allow_call_time_pass_reference] => 0
    [allow_url_fopen] => 1
    ...
)
Note:
ini_get_all() ignores "array" ini options such as pdo.dsn.*.