add boost on mac

macx64/include/boost/beast/core/file.hpp

@@ -0,0 +1,44 @@
+//
+// Copyright (c) 2015-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// Official repository: https://github.com/boostorg/beast
+//
+
+#ifndef BOOST_BEAST_CORE_FILE_HPP
+#define BOOST_BEAST_CORE_FILE_HPP
+
+#include <boost/beast/core/detail/config.hpp>
+#include <boost/beast/core/file_base.hpp>
+#include <boost/beast/core/file_posix.hpp>
+#include <boost/beast/core/file_stdio.hpp>
+#include <boost/beast/core/file_win32.hpp>
+
+namespace boost {
+namespace beast {
+
+/** An implementation of File.
+
+    This alias is set to the best available implementation
+    of <em>File</em> given the platform and build settings.
+*/
+#if BOOST_BEAST_DOXYGEN
+struct file : file_stdio
+{
+};
+#else
+#if BOOST_BEAST_USE_WIN32_FILE
+using file = file_win32;
+#elif BOOST_BEAST_USE_POSIX_FILE
+using file = file_posix;
+#else
+using file = file_stdio;
+#endif
+#endif
+
+} // beast
+} // boost
+
+#endif