The following code ensures that no user logged into the WordPress dashboard will see WordPress version update notices:
global $user_login;
get_currentuserinfo();
if ($user_login !== "admin") {
add_action( 'init', create_function( '$a', "remove_action( 'init', 'wp_version_check' );" ), 2 );
add_filter( 'pre_option_update_core', create_function( '$a', "return null;" ) );
}
Change “admin” to the username that should receive updates.
Alternative version that shows the update notice to all site administrators, not just the user named “admin”:
global $user_login;
get_currentuserinfo();
if (!current_user_can('update_plugins')) {
add_action( 'init', create_function( '$a', "remove_action( 'init', 'wp_version_check' );" ), 2 );
add_filter( 'pre_option_update_core', create_function( '$a', "return null;" ) );
}
This uses WordPress hooks. Learn more in WordPress Hooks Explained.