HelenOS sources

IOF_ABSOLUTE       56 uspace/app/vuhid/hids/bootkbd.c 	INPUT(IOF_DATA | IOF_VARIABLE | IOF_ABSOLUTE),
IOF_ABSOLUTE       67 uspace/app/vuhid/hids/bootkbd.c 	OUTPUT(IOF_DATA | IOF_VARIABLE | IOF_ABSOLUTE),
HelenOS homepage, sources at GitHub