EIEIO may refer to: The refrain to the children's song, "Old MacDonald Had a Farm" Enforce In-order Execution of I/O, a machine instruction used on the PowerPC computer processor Computer bought the farm, an error message with symbol EIEIO, from the GNU Hurd operating system EIEIO, the Enhanced Implementation of Emacs Interpreted Objects, an object-oriented elisp system based on the Common Lisp Object System "E-I-E-I-O", an episode of Barney & Friends from the fourth season of the show
See also "E-I-E-I-(Annoyed Grunt)", 1999 episode of The Simpsons