How to stop infinite yield/nil value?

I'm creating a simple coordinates gui but this one error keeps stopping it from working for most people. The script is:

plr = game.Players.LocalPlayer
char = plr:WaitForChild("Character")
while true do
	script.Parent.Text = tostring(math.ceil(char.Torso.Position.x)..", "..math.ceil(char.Torso.Position.y)..", "..math.ceil(char.Torso.Position.z))
	wait(0.1)
end

And I get the error that there is an "infinite yield" for the char variable, but before I made it WaitForChild it said that char was a "nil value." How do I make this work?