This gist contains an example of using Rcpp::XPter in R

Rcpp_XPter_example.R

# load packages
library(Rcpp)
library(testthat)

# define functions
cppFunction('
	Rcpp::List export_data(Rcpp::NumericVector x) {
		std::vector<double> x1 = Rcpp::as< std::vector<double> >(x);
		std::vector<double>* x2 = new std::vector<double>;
		*x2 = x1;
		Rcpp:XPtr< std::vector<double> > pointer(x2);
		return(Rcpp::List::create(Rcpp::Named("ptr") = pointer));
	}
')

cppFunction('
	Rcpp::NumericVector import_data(Rcpp::List x) {
		std::vector<double> x1 = *Rcpp::as< Rcpp::XPtr< std::vector<double> > >(x["ptr"]);
		return (Rcpp::wrap(x1));
	}
')

## main code
x = 1:10 # create initial R object
ptr = export_data(x) # sink R object to memory
x2 = import_data(ptr) # recover R object from memory
test_that('data has changed', expect_equal(x, x2)) # test that objects are the same