-Buffer * newUnnamedFile(std::string const & templatename,
- support::FileName const & path);
+Buffer * newUnnamedFile(support::FileName const & path,
+ std::string const & prefix, std::string const & templatename = "");
+
+/// Load the file with name \c fname, and returns the buffer. If the
+/// file was already loaded it just returns the associated buffer.
+Buffer * loadIfNeeded(support::FileName const & fname);