title: How to draw a line in a GtkDrawingArea using Cairo with Gtk3
body: <p>Could someone please show me a minimal working example of using C language for Cairo with Gtk3 to draw a single line in a <code>GtkDrawingArea</code>. I've tried to modify <code>testcairo.c</code> in the Gtk3 tests folder but I can't get it to work. Please don't suggest the tutorials at the Cairo site; Zetcode.com or gnome.org which are either not for use with Gtk3 or not minimal working examples.</p>