[Frank Verberne]

For anyone with the same problem, here's my solution I eventually used:

import viz
import vizact
import viztask

viz.go()

#CONSTANTS
TIMER_SPEED = 0.1
SEC_DELAY = 4

yaw_list = []
pitch_list = []
roll_list = [] 

def logTrackingData():
	orientation = viz.MainView.getEuler()
	yaw_list.append(orientation[0])
	pitch_list.append(orientation[1])
	roll_list.append(orientation[2])
	
def readTrackingData():
	global yaw, pitch, roll
	#Read information
	yaw = yaw_list[0]
	pitch = pitch_list[0]
	roll = roll_list[0]
	#Delete information already read
	yaw_list.pop(0)
	pitch_list.pop(0)
	roll_list.pop(0)

def readWithDelay():
	#Wait 4 seconds
	yield viztask.waitTime(SEC_DELAY)
	vizact.ontimer(TIMER_SPEED, readTrackingData)

vizact.ontimer(TIMER_SPEED, logTrackingData)
viztask.schedule(readWithDelay())