HelenOS sources

PROXIMITY_OUT     138 uspace/srv/hid/isdv4_tablet/isdv4.c 			event.type = PROXIMITY_OUT;
PROXIMITY_OUT     143 uspace/srv/hid/isdv4_tablet/isdv4.c 				event.type = PROXIMITY_OUT;
PROXIMITY_OUT     151 uspace/srv/hid/isdv4_tablet/isdv4.c 				event.type = PROXIMITY_OUT;
PROXIMITY_OUT     133 uspace/srv/hid/isdv4_tablet/main.c 	case PROXIMITY_OUT:

HelenOS homepage, sources at GitHub