libdatrwxx [WP]: set default for format modifiers in osffstream

src/libs/libdatrwxx/sff.h

@@ -33,6 +33,7 @@
  *  - 07/06/2011   V1.3   promise constness of series samples
  *  - 21/11/2011   V1.4   introduce format modifiers
  *  - 18/11/2016   V1.5   use debug flag in base class
+ *  - 22/11/2016   V1.6   set default for format modifiers
  * 
  * ============================================================================
  */
@@ -41,7 +42,7 @@
 #ifndef DATRW_SFF_H_VERSION
 
 #define DATRW_SFF_H_VERSION \
-  "DATRW_SFF_H   V1.5"
+  "DATRW_SFF_H   V1.6"
 
 #include<sffxx.h>
 #include<datrwxx/datread.h>
@@ -97,7 +98,7 @@ namespace datrw {
   class osffstream: public odatstream {
     public:
       typedef odatstream Tbase;
-      osffstream(std::ostream& os, const std::string& modifier,
+      osffstream(std::ostream& os, const std::string& modifier="",
                  const bool& debug=false);
       inline virtual ~osffstream() 
       { this->flushwaitingtrace(true); }