#include <iostream>
#include <boost/filesystem.hpp>

using boost::filesystem::path;
using std::cout;
using std::endl;
using std::ofstream;


int main(int argc, char** argv) {
	// Creates a directory symlink-example/dir containing a file hello.txt
	path tmp = boost::filesystem::temp_directory_path() / "symlink-example";
	boost::filesystem::remove_all(tmp);
	path myDir = tmp / "dir";
	boost::filesystem::create_directories(myDir);
	path myFile = myDir / "hello.txt";
	{
		ofstream filestream(myFile.string().c_str(), ofstream::out);
		filestream << "hello, world!" << endl;
	}

	// Creates a directory symlink symlink-example/sym -> symlink-example/dir
	path mySym = tmp / "sym";
	boost::filesystem::create_directory_symlink(myDir, mySym);

	// when cwd is a directory, c: is not considered a symlink and canonical works
	boost::filesystem::current_path(myDir);
	cout << "c: is symlink? " << boost::filesystem::is_symlink(path("c:")) << endl; // outputs 0
	boost::filesystem::canonical(myFile);

	// when cwd is the symlink to the directory, "c:" is considered a symlink to dir!
	boost::filesystem::current_path(mySym);
	cout << "c: is symlink? " << boost::filesystem::is_symlink(path("c:")) << endl; // outputs 1

	/*
	Canonical will enter an infinite loop. By way of example, assume 
		myDir  = c:\temp\symlink-example\dir
		mySym  = c:\temp\symlink-example\sym -> myDir
		myFile = c:\temp\symlink-example\dir\hello.txt
	It iterates over the path components of myFile (operations.cpp:827), starting with c:
	c: is considered a symlink (operations.cpp:844) with target myDir, so it expands it to
		c:\temp\symlink-example\dir\temp\symlink-example\dir\hello.txt
	scan is set true and the loop repeats, resulting in
		c:\temp\symlink-example\dir\temp\symlink-example\dir\temp\symlink-example\dir\hello.txt
	and so on in an infinite loop resulting in an infinitely expanding path.
	*/
	boost::filesystem::canonical(myFile);
}