flymake-cursor.el module displays the flymake error in the minibuffer after a short delay. It is based on code the author found roaming around on the net, unsigned and unattributed. It is assumed to be public domain, because while there is a "License" listed in it, there is no license holder (no one to own the license). This version is modified slightly from that code. The post-command fn defined in this code does not display the message directly. Instead it sets a timer, and when the timer fires, the timer event function displays the message. The reason to do this: the error message is displayed only if the user doesn't do anything, for about one second. This way, if the user scrolls through a buffer and there are myriad errors, the minibuffer is not constantly being updated. If the user moves away from the line with the flymake error message before the timer expires, then no error is displayed in the minibuffer.