Function gmp_mpfr_sys::gmp::mpf_get_str

pub unsafe extern "C" fn mpf_get_str(
    str: *mut c_char, 
    expptr: *mut exp_t, 
    base: c_int, 
    n_digits: usize, 
    op: *const mpf_t
) -> *mut c_char

See: mpf_get_str