19:32, 26 June 2015 (diff | hist) . .(-8) . . m Function Reference/get userdata (actual user_meta fields are first_name and last_name, and these values are required when you use wp_update_user() (i.e., user_firstname and user_lastname do not work there).)
19:05, 28 May 2015 (diff | hist) . .(+73) . . m Function Reference/update user meta (update_user_meta() returns false if the value trying to be saved matches the existing value. See https://wordpress.org/support/topic/update_user_meta-failure-conditions?replies=3)