[cairo] writing multiple surfaces to a single (pdf) file

[Zoltán Vörös]

Hi All,

I would like to ask how one can save multiple surfaces into a single pdf 
file. I know how to save a single surface, but what if I would like to 
write two surfaces to two pages of a pdf file. One example could be if I 
save the original surface, then modify, and then save the new surface. 
Is this possible, or one has to concatenate the pdf files outside?
Thanks,
Zoltán