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README.md

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+# mio
+A simple header-only cross-platform C++14 memory mapping library.
+
+## Example
+```c++
+#include <mio/mmap.hpp>
+#include <system_error> // for std::error_code
+#include <cstdio> // for std::printf
+
+// This is just to clarify which is which when using the various mapping methods.
+using offset_type = mio::mmap_source::size_type;
+using length_type = mio::mmap_source::size_type;
+
+int handle_error(const std::error_code& ec)
+{
+    const auto& errmsg = error.message();
+    std::printf("error mapping file: %s, exiting...\n", errmsg.c_str());
+    return error.value();
+}
+
+int main()
+{
+    // Read-only memory map the whole file by using `use_full_file_size` where the
+    // length of the mapping would otherwise be expected, with the factory method.
+    std::error_code error;
+    mio::mmap_source mmap1 = mio::make_mmap_source("log.txt",
+        offset_type(0), mio::mmap_source::use_full_file_size, error);
+    if(error) { return handle_error(error); }
+
+    // Read-write memory map the beginning of some file using the `map` member function.
+    mio::mmap_sink mmap2;
+    mmap2.map("some/path/to/file", offset_type(0), length_type(2342), error);
+    if(error) { return handle_error(error); }
+
+    // Iterate through the memory mapping just as if it were any other container.
+    for(auto& c : mmap2) {
+        // Since this is a read-write mapping, we can change c's value.
+        c += 10;
+    }
+
+    // Or just change one value with the subscript operator.
+    mmap2[mmap2.size() / 2] = 42;
+
+    // Or map using the constructor, which throws a std::error_code upon failure.
+    try {
+        mio::mmap_sink mmap3("another/path/to/file", offset_type(4096), length_type(4096));
+        // ...
+    } catch(const std::error_code& error) {
+        return handle_error(error);
+    }
+}
+```
+
+# Installation
+mio is a header-only library, so just copy the contents in `mio/include` into your system wide include path, such as `/usr/include`, or into your project's lib folder.
+