Occasionally service messages are broadcast to all users of the system. On the TransPDF website these messages appear at the top of every page until dismissed by the user. They may contain notices of pending service interruptions and price changes.
Gets all the system messages not yet marked as read for the specific user. The id of each may be used to dismiss it with the dismiss_sys_message() call.
A list of 3-tuples - [(id, title, message)...]
Marks the message whose ID is msg_id as read. After this call the message will never be delivered to this user again.