How to get printer status via CUPS API?

[Toni Heimala]

How can I get the current printer status through the CUPS API?

What I would like to achieve is to get printer status messages like "Out 
of paper", "Paper jam", etc.

I have tried calling the cupsLastErrorString() function for example but 
it only returns "successfull-ok" after I've sent a file for printing via 
the cupsPrintFile() function. Even though the printer is actually in out 
of paper state.