Adding symbol FN_DIRSEP to Windows as well.
@ -611,6 +611,7 @@ typedef SOCKET_SIZE_TYPE size_socket;
#ifdef _WIN32
#define FN_LIBCHAR '\\'
#define FN_LIBCHAR2 '/'
#define FN_DIRSEP "/\\" /* Valid directory separators */
#define FN_ROOTDIR "\\"
#define FN_DEVCHAR ':'
#define FN_NETWORK_DRIVES /* Uses \\ to indicate network drives */