in the CVS tree (root = "control"),
the OPLE server lives in control/modules/ople

in the file "control/modules/ople_comms.c", commands are send via a function
called "send_ople_command" --- here's the header
/************************************************************************/
/* send_ople_command()                                                  */
/*                                                                      */
/* Tries to send the ople command structure, assumed filled in already  */
/* down the ople socket. Before sending it makes sure this is one of    */
/* the allowed commands and if so does a byte reversal on all fields    */
/* Since SParcs, MPPs and Linux use different byte orders. It then tries*/
/* to send the command. Returns TRUE if it works and FALSE otherwise.   */
/************************************************************************/

bool send_ople_command(ISIT_CMD command, int iGizmoId)


The JPL code for the oples lives in /ctrscrut/chara/jpl_code.  Theo says to
look for references to TT_FT.  Brad Hines is a good contact.