What is the meaning of client coordinates in SetWindowPos

Question

The documentation for SetWindowPos says the following for the X and Y parameters:

X [in]

Type: int

The new position of the left side of the window, in client coordinates.

Y [in]

Type: int

The new position of the top of the window, in client coordinates.

By "client coordinates", does it mean that the parameters specify the position of the client area of the window, or that they specify the position of the window (not the client area) relative to the parent window's client area? Or something else?

Answer 1

It's your second proposition: The position of the window in its parent's client area.