[cairo] How to load a font from a *.ttf file?

[Carlo]

Hi,
how can I load a TrueType Font in cairo? I need to render some test on a 
surface (DirectFB backend, but I think that is not relevant), using a 
monospaced font. I tried Pango libraries, but it takes the font from 
FontConfig and I can't properly configure the width an height of the 
font, I can't resize the font to fit in a precise logical extent. Cairo 
scaled font seems to be useful for my purpose, but I don't understand 
how to load a *ttf.
Thank you in advance
Carlo