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or else use the -width and -height options to specify the area of the canvas to print.
-pageanchor => anchor

Specifies which point of the printed area of the canvas should appear over the positioning point on the page (which is given by the -pagex and -pagey options). For example, -pageanchor=>n means that the top center of the area of the canvas being printed (as it appears in the canvas window) should be over the positioning point. Defaults to center.