+/// check for characters in filenames not allowed by LaTeX
+bool isValidLaTeXFileName(std::string const & filename);
+
+/** check for characters in filenames that might lead to
+ problems when manually compiling the LaTeX export of LyX
+ and opening the result with some older DVI-viewers
+*/
+bool isValidDVIFileName(std::string const & filename);
+
+/// check whether the file has binary contents
+bool isBinaryFile(FileName const & filename);