The current security settings do not allow downloading of this file. The four most commonly used ini functions in PHP configuration files

The configuration function of PHP is several ini_* functions, mainly for the operation of configuration files. In fact, there are four functions: ini_get, ini_set, ini_get_all, and ini_restore. Personally, the most useful ones are ini_set and ini_get.
* ini_get(): Get the option value of the configuration file. I believe many people have used this function. It is to get the value of an option in the configuration file. If it is a true value, it returns 1. If it is a false value, it returns 0. Character String returns a string.
For example, the example in the manual:
/*
Our php.ini contains the following settings:
display_errors = On
register_globals = Off
post_max_size = 8M
*/
echo 'display_errors = ' . ini_get(' display_errors') . "n"; //Whether display errors are turned on
echo 'register_globals = ' . ini_get('register_globals') . "n"; //Whether global variables are turned on
echo 'post_max_size = ' . ini_get('post_max_size' ) . "n";//The maximum file size that can be submitted
echo 'post_max_size+1 = ' . (ini_get('post_max_size')+1) . "n";
?>
Output:
display_errors = 1
register_globals = 0
post_max_size = 8M
post_max_size+1 = 9
This function is mainly used to obtain the configuration file, which can facilitate many operations for you. For example, you want to operate string filtering, but you don’t know whether magic_quotes_gpc is turned on, so you can write a function like this:
/* String filtering function */
function stringFilter($str)
{
if (ini_get(' magic_quotes_gpc)') {
return $str;
} else {
return addslashes($str);
}
}
Of course, if you have no way of knowing whether your global variable is open, you can also customize such a function:
/* Variable detection function */
function getGetVar($var)
{
if (ini_set('register_gobals')) {
return $var;
} else {
return $_GET['var'];
}
}
Of course , you can use it for many purposes, and you will slowly experience it yourself.
* ini_set function: Set certain variable values ​​in php.ini
This function is to set the value in the option. It takes effect after the function is executed. When the script ends, this setting also becomes invalid. Not all options can be set by the function. Specific values ​​​​can be set, you can view the list in the manual.
It means you can set the option value in php.ini. For example, the display_error option is turned off, but you want to display the error message in the program to facilitate your debugging the program, then you can use this function:
ini_set("display_errors", "On" );
Then the program on your page will display error information, and you can also use error_reporting to set the level of error information displayed.
If you need to increase the script execution time, you can set:
ini_set("max_execution_time", "180");
Then the script execution time will change from the default 30 seconds to 180 seconds. Of course, you can also use set_time_limit() to set.
Actually, it’s very good if you combine ini_set and ini_get. For example, if you want to add your own include file path to the configuration file, but do you have permission to change php.ini, then you can combine two functions:
ini_set('include_path',ini_get('include_path').':/your_include_dir :');
* ini_get_all: Get all setting option variables
Return all option values ​​​​in the form of an array, which is convenient for you to use when phpinfo() cannot be used.
Manual example, such as:
$inis = ini_get_all();
print_r($inis);
?>
Partial output:
Array
(
[allow_call_time_pass_reference] => Array
(
 [ global_value] => 1
[local_value] => 1
[access] => 6
)
[allow_url_fopen] => Array
(
[glo ] bal_value] => 1
[local_value] => 1 S [access] = & gt; 7
)
...
)
*ini_restore: Reply to the default value of the configuration file
is to reply to the default value of the configuration file. When you use ini_set settings, you can use it to recover.

The above introduces the four most commonly used ini functions in the PHP configuration file that do not allow the file to be downloaded by the current security settings, including the content that the file is not allowed to be downloaded by the current security settings. I hope it will be helpful to friends who are interested in PHP tutorials.