Are there any built-in PHP functions that can simplify the process of updating configuration variables in a file?

When updating configuration variables in a file, it can be cumbersome to manually open the file, find the variable, update its value, and save the changes. One way to simplify this process is to use the `parse_ini_file()` and `parse_ini_string()` functions in PHP. These functions can read an INI file or string and return an associative array of configuration variables, which can then be updated and written back to the file using `file_put_contents()`.

// Read the configuration file into an associative array
$config = parse_ini_file('config.ini');

// Update the desired configuration variable
$config['variable_name'] = 'new_value';

// Convert the array back to an INI string
$ini_string = '';
foreach ($config as $key => $value) {
    $ini_string .= "$key = $value\n";
}

// Write the updated configuration back to the file
file_put_contents('config.ini', $ini_string);