wp_save_image_file in /wp-admin/includes/image-edit.php
4079
Continue readingGet salt to add to hashes to help prevent attacks.The secret key is located in two places: the database in case the secret key isn’t defined in the second place, which is in the wp-config.php file. If you are going to set the secret key, then you must do so in the wp-config.php file.
4073
Continue readingPerforms a safe (local) redirect, using wp_redirect().Checks whether the $location is using an allowed host, if it has an absolute path. A plugin can therefore set or remove allowed host(s) to or from the list.
4071
Continue reading