[cairo] How can I find out where the line start in cairo_line_to

[ying lcs]

Hi,

Can you  please tell me if there is an api from cairo which I can call
to find out where will the line start if I call cairo_line_to()?

 cairo_line_to(mCairo, pt.x, pt.y);

I have the above call in my code, but I am not sure where does the
line start, I lost track of where did I move the starting point to.

And how many ways I can change the starting point of cairo_line_to?
The only way i know is cairo_move_to? is there anything else?

Thank you.