HelenOS sources

KC_F3             142 uspace/drv/hid/adb-kbd/ctl.c 	[0x63] = KC_F3,
KC_F3             129 uspace/drv/hid/atkbd/atkbd.c 	[0x04] = KC_F3,
KC_F3             108 uspace/drv/hid/usbhid/kbd/conv.c 	[0x3c] = KC_F3,
KC_F3             121 uspace/drv/hid/xtkbd/xtkbd.c 	[0x3d] = KC_F3,
KC_F3             597 uspace/lib/vt/src/vt100.c 		vt100_key(vt, 0, KC_F3, 0);
KC_F3             204 uspace/srv/hid/input/ctl/stty.c 	0,	KC_F3,		0x1b, 0x4f, 0x52, GSP_END,
KC_F3             106 uspace/srv/hid/input/ctl/sun.c 	[0x08] = KC_F3,
KC_F3             221 uspace/srv/hid/input/input.c 		case KC_F3:
HelenOS homepage, sources at GitHub