I am using wordpress functions in a custom php file including
wp-load.php, run from browser it is fine, but run from command line with
wp-load.php causes problems:
Warning: Cannot modify header information - headers already sent in /../wp-includes/ms-settings.php on line 162
code example to reproduce:
echo 'something'; require "/../wp-load.php";
echo, you send headers, so you can not send them again or modified them. This is a pure PHP related problem not specifically related with WordPress.