Technique for using std::ifstream, std::ofstream in python via SWIG?

Question

Is there a way to use std::[io]fstream\'s in python via swig?

I have a c-class with functions like:

void readFrom(std::istream& istr         


        

Answer 1

I ended up just writing my own proxy class for use within the interface. So I used SWIG to wrap this class:

 /**
 * Simple class to expose std::streams in the python
 * interface.  works around some issues with trying to directy
 * the file stream objects
 */
class ifstream_proxy: boost::noncopyable{
    public:
        ifstream_proxy(): m_istr(){
            // no op
        }
        virtual ~ifstream_proxy(){
            // no op
        }
        void open(const std::string& fname ){
            m_istr.close(); 
            m_istr.open( fname.c_str(), std::ifstream::in|std::ifstream::binary) ;
        }
        std::istream& stream(){
            return m_istr;
        }
        // TBD: do I want to  add additional stream manipulation functions?
   private: 
        std::ifstream m_istr;
};

and in python call make the calls

>>> proxy=ifstream_proxy()
>>> proxy.open('file_to_read_from.txt')
>>> readFrom( stream_proxy.stream() )