HelenOS sources

KC_PAUSE          156 uspace/drv/hid/adb-kbd/ctl.c 	[0x71] = KC_PAUSE,
KC_PAUSE          121 uspace/drv/hid/usbhid/kbd/conv.c 	[0x48] = KC_PAUSE,
KC_PAUSE          167 uspace/drv/hid/xtkbd/xtkbd.c 	[0x46] = KC_PAUSE,
KC_PAUSE          291 uspace/drv/hid/xtkbd/xtkbd.c 				push_event(kbd->client_sess, evtype, KC_PAUSE);
KC_PAUSE          974 uspace/lib/vt/src/vt100.c 		vt100_key(vt, 0, KC_PAUSE, 0);
KC_PAUSE          216 uspace/srv/hid/input/ctl/stty.c 	0,	KC_PAUSE,	0x1b, 0x5b, 0x32, 0x38, 0x7e, GSP_END,
KC_PAUSE          119 uspace/srv/hid/input/ctl/sun.c 	[0x15] = KC_PAUSE,
HelenOS homepage, sources at GitHub