[Boost-users] [program-options] Problem with paths that have spaces

25 Aug 2008

      Hi all,

I'm trying to use program-options to specify a filesystem path object  
under Boost 1.35.0. The following code works fine when the path  
specified on the command line has no spaces in it. But when it does  
have spaces, I get an error.

--snip--

#include <iostream>
#include <sstream>

#include <boost/program_options.hpp>
#include <boost/filesystem/path.hpp>

namespace po = boost::program_options;
namespace fs = boost::filesystem;

using namespace std;

int main (int argc, char * argv[])
{
	int result = 0;

	try
	{
		fs::path inPath;

		po::options_description desc("Allowed options");
		desc.add_options()
		("in,i", po::value<fs::path>(&inPath), "Input file or directory  
<pathname>")
		;

		po::variables_map vm;
		po::store(po::parse_command_line(argc, argv, desc), vm);
		po::notify(vm);

		if (0 ==vm.count("in"))
		{
			throw invalid_argument("What? No input path specifed!");
		}

		cout << "Input path = \"" << inPath.file_string() << "\"\n";
	}
	catch(const boost::filesystem::filesystem_error& e)
	{
		cerr << "\nFilessytem error: " << e.what() << endl;
		result = 3;
	}
	catch(const std::exception& e)
	{
		cerr << "\nException error: " << e.what() << endl;
		result = 2;
	}
	catch(...)
	{
		cerr << "\nError: Caught an unknown exception!" << endl;
		result = 1;
	}

	return result;
}

--snip--

If I call the above with the following parameters, it works:

	--in "my_file"

	Input path = "my_file"

But if I call it with a path that has a space in it, I get an error:

	--in "my file"

	Exception error: in option 'in': invalid option value 'my file'

I know that I can work around the problem by loading the path into an  
interim string first, then use the string to initialize a path object.  
But unless I'm missing something, I would have thought that  
iteroperability between boost.program-options and boost.filesystem  
should be more seamless. It seems very common to want to load options  
into path objects.

Best,
--
Allen Cronce