A self-contained, header-only, implementation of memory-mapped files in C++
for both reading and writing.
This is meant to offer the same capability of boost::mapped_file (source and sink) but avoiding
the dependance from boost.
Example usage.
#include <iostream>
#include "../include/mm_file/mm_file.hpp"
int main() {
std::string filename("./tmp.bin");
static const size_t n = 13;
{
// write n uint32_t integers
mm::file_sink<uint32_t> fout(filename, n);
std::cout << "mapped " << fout.bytes() << " bytes "
<< "for " << fout.size() << " integers" << std::endl;
auto* data = fout.data();
for (uint32_t i = 0; i != fout.size(); ++i) {
data[i] = i;
std::cout << "written " << data[i] << std::endl;
}
fout.close();
}
{
// instruct the kernel that we will read the content
// of the file sequentially
int advice = mm::advice::sequential;
// read the stream as uint16_t integers
mm::file_source<uint16_t> fin(filename, advice);
std::cout << "mapped " << fin.bytes() << " bytes "
<< "for " << fin.size() << " integers" << std::endl;
auto const* data = fin.data();
for (uint32_t i = 0; i != fin.size(); ++i) {
std::cout << "read " << data[i] << std::endl;
}
fin.close();
}
std::remove(filename.c_str());
return 0;
}See also the example in test/test.cpp. To compile that, just type the following commands from the parent directory.
$ cd test
$ mkdir build
$ cd build
$ cmake ..
$ make