Clarified occasions of -mark message and removed surplus -mark message emitter

xorriso/parse_exec.c

@@ -1395,8 +1395,6 @@ eval_any_problems:
    goto next_command;
 
 ex:;
- if((!xorriso->is_dialog) && !(flag&1))
-   Xorriso_mark(xorriso,0);
  fflush(stdout);
  return(ret);
 }

xorriso/xorriso.texi

@@ -4494,8 +4494,9 @@ channels, "I" for info messages, "R" for result lines, "M" for -mark texts.
 @item -mark text
 @kindex -mark   sets synchronizing message
 @cindex Process, set synchronizing message, -mark
-If text is not empty it will get put out on "M" channel each time after a
-dialog line has been processed.
+If text is not empty it will get put out on "M" channel each time xorriso
+is ready for the next dialog line or before xorriso performs a command that
+was entered to the pager prompt.
 @c man .TP
 @item -prog text
 @kindex -prog   sets program name

xorriso/xorriso_timestamp.h

@@ -1 +1 @@
-#define Xorriso_timestamP "2010.11.30.112050"
+#define Xorriso_timestamP "2010.11.30.170112"