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#include "afio_pch.hpp"
//[closure_execution_afio_example
#include <vector>
int main()
{
const int ary_size = 10;
//set up a file to read from
std::ofstream out_file("somefile.dat", std::ios::binary);
for (int i = 0; i < ary_size; ++i)
{
out_file.write(reinterpret_cast<const char*>(&i), sizeof(i));
}
out_file.close();
//set up the afio dispatcher
auto dispatcher = boost::afio::make_dispatcher().get();
//set up an array to hold our integers
int ary[ary_size];
//schedule the file open
auto opened_file = dispatcher->file(boost::afio::path_req("somefile.dat",
boost::afio::file_flags::read));
//set up vectors for the individual read operations, and the work on each integer
std::vector<boost::afio::future<>> read_ops(ary_size);
std::vector<std::function<void()>> vec_func(ary_size);
for (int i = 0; i < ary_size; ++i)
{
read_ops[i] = dispatcher->read(boost::afio::io_req<int>(opened_file,
&ary[i], sizeof(int), i*sizeof(int)));
vec_func[i] = std::bind([](int* a){ *a *= 2 ; }, &ary[i]);
}
// schedule the work to be done after reading in an integer
auto work = dispatcher->call(read_ops, vec_func);
//schedule the file to be closed after reads are finished
auto closed_file = dispatcher->close(dispatcher->barrier(read_ops).front());
// make sure work has completed before trying to print data from the array
boost::afio::when_all_p(work.begin(), work.end()).wait();
//verify the out put is as expected: "0, 2, 4, 6, 8, 10, 12, 14, 16, 18"
for (int i = 0; i < ary_size; ++i)
{
std::cout << ary[i];
if(i == ary_size-1)
std::cout << std::endl;
else
std::cout << ", ";
}
return 0;
}
//]
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