// In header: <boost/filesystem/operations.hpp>


struct space_info {

  // public data members
  boost::uintmax_t capacity;  // Total size of the filesystem, in bytes. 
  boost::uintmax_t free;  // Amount of free space, in bytes. 
  boost::uintmax_t available;  // Amount of free space available for unprivileged users, in bytes. 
};