<warning>
until i load more .ini files from <php-dir>/php.d/ as listed in phpinfo() (sections "Scan this dir for additional .ini files" and "Additional .ini files parsed"), php_ini_scanned_files() returns me NOTHING!
then i realized my php binary was not compiled with the "--with-config-file-scan-dir" option as listed in phpinfo() (section "Configure Command")
then i remembered the additional .ini files dir was set through the "PHP_INI_SCAN_DIR" system variable (new since php 5.2.0, see https://php.net/manual/en/configuration.file.php#configuration.file.scan)
until confusing and annoying, is the documented behavior... too bad now i don't know how to get the additional ini files purely with php functions (except "shell_exec()" maybe?)
</warning>