title: What is the type of mpfr_t and how do I make a C function of this type?
body: <p>I've just started using the GMP and MPFR. I'm writing a program in C and would like to make a function that (for example) takes as input an mpfr_t variable and returns an mpfr_t variable. I'm not sure of the definition of mpfr_t, but I tried naively doing this and get compile errors.</p>
  
  <p>Any information regarding this would be much appreciated.</p>