Question about using a C application with FastCGI

Hi,

I am new to FastCGI, i would like to know if I use a C application
with FastCGI,  my understanding is FastCGI will spawn a process
running my C application for each request it gets. Is that correct?

If yes, how can I make FastCGI to use the same instance of my C
application for all the subsequence requests from the same user?

Thank you.