diff --git a/libisoburn/trunk/libisoburn/isoburn.c b/libisoburn/trunk/libisoburn/isoburn.c
index 61623e7c..3af7a1f6 100644
--- a/libisoburn/trunk/libisoburn/isoburn.c
+++ b/libisoburn/trunk/libisoburn/isoburn.c
@@ -326,6 +326,7 @@ int isoburn_prepare_disc_aux(struct burn_drive *d, struct burn_disc **disc,
  
  if (new_img) {
    iso_write_opts_set_ms_block(wopts, 0);
+   opts->effective_lba= 0;
    iso_write_opts_set_appendable(wopts, 0);
    iso_write_opts_set_overwrite_buf(wopts, NULL);
  } else {
@@ -343,6 +344,7 @@ int isoburn_prepare_disc_aux(struct burn_drive *d, struct burn_disc **disc,
      {ret= -4; goto ex;}
    }
    iso_write_opts_set_ms_block(wopts, nwa);
+   opts->effective_lba= nwa;
    iso_write_opts_set_appendable(wopts, 1);
    iso_write_opts_set_overwrite_buf(wopts, o->target_iso_head);
  }
@@ -678,6 +680,7 @@ int isoburn_igopt_new(struct isoburn_imgen_opts **new_o, int flag)
  o->gid= 0;
  o->output_charset= 0;
  o->fifo_size= 4*1024*1024;
+ o->effective_lba= -1;
  return(1);
 }
 
@@ -837,3 +840,10 @@ int isoburn_igopt_get_fifo_size(struct isoburn_imgen_opts *o, int *fifo_size)
 }
 
 
+int isoburn_igopt_get_effective_lba(struct isoburn_imgen_opts *o, int *lba)
+{
+ *lba= o->effective_lba;
+ return(1);
+}
+
+
diff --git a/libisoburn/trunk/libisoburn/isoburn.h b/libisoburn/trunk/libisoburn/isoburn.h
index d613f68b..e22ee55c 100644
--- a/libisoburn/trunk/libisoburn/isoburn.h
+++ b/libisoburn/trunk/libisoburn/isoburn.h
@@ -319,6 +319,13 @@ struct isoburn_imgen_opts {
     */
     int fifo_size;
 
+
+    /** Output value: Block address of session start as evaluatedfrom media
+                      and other options by libisoburn and libburn.
+        If <0 : Invalid
+        If >=0: Valid block number. Block size is always 2 KiB.
+    */
+    int effective_lba;
 };
 
 #endif /* Isoburn_includeD */
diff --git a/libisoburn/trunk/libisoburn/libisoburn.h b/libisoburn/trunk/libisoburn/libisoburn.h
index 0e1a8e76..17ac7f63 100644
--- a/libisoburn/trunk/libisoburn/libisoburn.h
+++ b/libisoburn/trunk/libisoburn/libisoburn.h
@@ -723,6 +723,18 @@ int isoburn_igopt_set_fifo_size(struct isoburn_imgen_opts *o, int fifo_size);
 int isoburn_igopt_get_fifo_size(struct isoburn_imgen_opts *o, int *fifo_size);
 
 
+/** Obtain after image preparation the block address where the session will
+    start on media.
+    This value cannot be set by the application but only be inquired.
+    @since 0.1.4
+    @param o          The option set to work on
+    @param lba        The block number of the session start on media.
+                      <0 means that no address has been determined yet.
+    @return 1 success, <=0 failure
+*/
+int isoburn_igopt_get_effective_lba(struct isoburn_imgen_opts *o, int *lba);
+
+
 /* ----------------------------------------------------------------------- */
 /*                      End of Options for image generation                */
 /* ----------------------------------------------------------------------- */
diff --git a/libisoburn/trunk/xorriso/xorriso.1 b/libisoburn/trunk/xorriso/xorriso.1
index 9f455423..f3b232f1 100644
--- a/libisoburn/trunk/xorriso/xorriso.1
+++ b/libisoburn/trunk/xorriso/xorriso.1
@@ -2,7 +2,7 @@
 .\" First parameter, NAME, should be all caps
 .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 .\" other parameters are allowed: see man(7), man(1)
-.TH XORRISO 1 "March, 29, 2008"
+.TH XORRISO 1 "April, 3, 2008"
 .\" Please adjust this date whenever revising the manpage.
 .\"
 .\" Some roff macros, for reference:
@@ -1559,6 +1559,17 @@ some input file arguments might not have been processed at all.
 The errfile paths are transported as messages of very low priority "ERRFILE".
 This transport becomes visible with -report_about "ALL".
 .TP
+\fB\-session_log\fR path
+If path is not empty it gives the address of a plain text file where
+a log record gets appended after each session. This log can be used to
+determine the start_lba of a session for mount option sbsector= from
+date or volume id. With non-multi-session media this is currently the only
+way to obtain this parameter.
+.br
+Record format is: timestamp start_lba size volume-id
+.br
+The first three items are single words, the rest of the line is the volume id.
+.TP
 \fB\-end\fR
 .br
 End program immediately
@@ -1849,11 +1860,12 @@ DVD-R, DVD+R if the full backup leaves substantial remaining capacity
 on media and if the expected changes are much smaller than the full backup.
 An update run will probably save no time but last longer than a full backup.
 .br 
-With overwriteable media like DVD+RW or disk files, the older backup versions
-cannot be retrieved. But with multi-session media and mount option "sbsector="
-it is possible to access the session trees which represent the older backup
-versions. sbsector of a session is its "data   lba:" number from xorriso
-option -toc.
+With \fBmount\fR option \fB"sbsector="\fR it is possible to access the session
+trees which represent the older backup versions. Multi-session media can tell
+the sbsector by xorriso option -toc, as "data   lba:". For other media one
+may set before writing a suitable path for xorriso option -session_log where
+the sbsector number gets recorded as the second word in each line.
+.br
 With CD media, Linux mount accepts session numbers directly by its option
 "session=".
 .br
diff --git a/libisoburn/trunk/xorriso/xorriso.c b/libisoburn/trunk/xorriso/xorriso.c
index c3229b36..f0c802a4 100644
--- a/libisoburn/trunk/xorriso/xorriso.c
+++ b/libisoburn/trunk/xorriso/xorriso.c
@@ -1491,6 +1491,7 @@ completed:;
 
 
 /* @param flag bit0=with year and seconds
+               bit1=timestamp format YYYY.MM.DD.hhmmss
 */
 char *Ftimetxt(time_t t, char timetext[40], int flag)
 {
@@ -1504,6 +1505,10 @@ char *Ftimetxt(time_t t, char timetext[40], int flag)
  rpt[0]= 0;
  if(tmpt==0)
    sprintf(rpt+strlen(rpt), "%12.f", (double) t);
+ else if (flag&2)
+   sprintf(rpt+strlen(rpt), "%4.4d.%2.2d.%2.2d.%2.2d%2.2d%2.2d",
+           1900+tms.tm_year, tms.tm_mon, tms.tm_mday,
+           tms.tm_hour, tms.tm_min, tms.tm_sec);
  else if (flag&1)
    sprintf(rpt+strlen(rpt), "%2d %3s %4.4d %2.2d:%2.2d:%2.2d",
            tms.tm_mday, months[tms.tm_mon], 1900+tms.tm_year,
@@ -2971,8 +2976,11 @@ int Xorriso_new(struct XorrisO ** xorriso,char *progname, int flag)
  m->global_uid= 0;
  strcpy(m->volid, "ISOIMAGE");
  m->loaded_volid[0]= 0;
- m->publisher[0]= 0;
  m->volid_default= 1;
+ m->publisher[0]= 0;
+ m->session_logfile[0]= 0;
+ m->session_lba= -1;
+ m->session_blocks= 0;
  m->do_global_gid= 0;
  m->global_gid= 0;
  m->do_global_mode= 0;
@@ -4287,6 +4295,12 @@ int Xorriso_status(struct XorrisO *xorriso, char *filter, FILE *fp, int flag)
  sprintf(line,"-report_about %s\n",xorriso->report_about_text);
  if(!(is_default && no_defaults))
    Xorriso_status_result(xorriso,filter,fp,flag&2);
+
+ is_default= (xorriso->session_logfile[0]==0);
+ sprintf(line,"-session_log %s\n",
+         Text_shellsafe(xorriso->session_logfile,sfe,0));
+ if(!(is_default && no_defaults))
+   Xorriso_status_result(xorriso,filter,fp,flag&2);
  
  is_default= (strcmp(xorriso->return_with_text,"SORRY")==0 &&
               xorriso->return_with_value==32);
@@ -7760,6 +7774,37 @@ ex:;
  return(1);
 }
 
+
+int Xorriso_write_session_log(struct XorrisO *xorriso, int flag)
+{
+ FILE *fp= NULL;
+ char sfe[5*SfileadrL], timetext[40], *rpt, *wpt;
+
+ if(xorriso->session_logfile[0]==0)
+   return(2);
+ fp= fopen(xorriso->session_logfile, "a");
+ if(fp==0) {
+   sprintf(xorriso->info_text, "-session_log: Cannot open file %s",
+           Text_shellsafe(xorriso->session_logfile, sfe, 0));
+   Xorriso_msgs_submit(xorriso, 0, xorriso->info_text, 0, "FAILURE", 0);
+   return(0);
+ }
+ wpt= sfe;
+ for(rpt= xorriso->volid; *rpt!=0; rpt++) {
+   if(*rpt=='\n') {
+     *(wpt++)= '\\';
+     *(wpt++)= 'n';
+   } else
+     *(wpt++)= *rpt;
+ }
+ *wpt= 0;
+ fprintf(fp, "%s %d %d %s\n",
+         Ftimetxt(time(0), timetext, 2), xorriso->session_lba,
+         xorriso->session_blocks, sfe);
+ fclose(fp);
+ return(1);
+}
+
  
 /* ---------------------------- Options API ------------------------ */
 
@@ -8468,6 +8513,7 @@ int Xorriso_option_commit(struct XorrisO *xorriso, int flag)
  Xorriso_process_errfile(xorriso, 0, "burn session end", 0, 1);
  if(ret<=0)
    return(ret);
+ Xorriso_write_session_log(xorriso, 0);
  xorriso->volset_change_pending= 0;
  xorriso->no_volset_present= 0;
  if(flag&1)
@@ -9520,7 +9566,7 @@ int Xorriso_option_help(struct XorrisO *xorriso, int flag)
 "              exit_value may be 0 or 32 to 63.",
 "  -report_about severity   Set the threshhold for events to be reported.",
 "              Use -abort_on severities or: HINT, NOTE, UPDATE, DEBUG, ALL",
-"  -dialog     after all arguments are processed, enter dialog mode.",
+"  -dialog     After all arguments are processed, enter dialog mode.",
 "              In this mode you may enter searchtexts or any of the options",
 "              described here. One per line.",
 "  -dialog_reset  Revoke -dialog (works only if given as argument)",
@@ -9572,6 +9618,9 @@ int Xorriso_option_help(struct XorrisO *xorriso, int flag)
 "              Wait for Enter key resp. for a line of input at stdin.",
 "  -errfile_log mode path|channel",
 "              Log disk paths of files involved in problem events.",
+"  -session_log path",
+"              Set path of a file where a log record gets appended after",
+"              each session. Form: timestamp start_lba size volume-id", 
 "  # any text  Is ignored. In dialog mode the input line will be stored in",
 "              the eventual readline history, nevertheless.", 
 "  -version    Tell program and version number",
@@ -10508,6 +10557,15 @@ int Xorriso_option_rollback(struct XorrisO *xorriso, int flag)
 }
 
 
+/* Option -session_log */
+int Xorriso_option_session_log(struct XorrisO *xorriso, char *path, int flag)
+{
+ if(Sfile_str(xorriso->session_logfile, path, 0)<=0)
+   return(-1);
+ return(1);
+}
+
+
 /* Option -speed */
 int Xorriso_option_speed(struct XorrisO *xorriso, char *speed, int flag)
 {
@@ -11244,6 +11302,10 @@ next_command:;
    if(end_ret!=2)
      {ret= 3; goto ex;}
 
+ } else if(strcmp(cmd,"session_log")==0) {
+   (*idx)++;
+   ret= Xorriso_option_session_log(xorriso, arg1, 0);
+ 
  } else if(strcmp(cmd,"speed")==0) {
    (*idx)++;
    ret= Xorriso_option_speed(xorriso, arg1, 0);
diff --git a/libisoburn/trunk/xorriso/xorriso_private.h b/libisoburn/trunk/xorriso/xorriso_private.h
index caa388f3..bbd97908 100644
--- a/libisoburn/trunk/xorriso/xorriso_private.h
+++ b/libisoburn/trunk/xorriso/xorriso_private.h
@@ -104,6 +104,10 @@ struct XorrisO { /* the global context of xorriso */
 
  char publisher[129];
 
+ char session_logfile[SfileadrL];
+ int session_lba;
+ int session_blocks;
+
  /* >>> put libburn/isoburn aspects here */
 
  char indev[SfileadrL];
diff --git a/libisoburn/trunk/xorriso/xorriso_timestamp.h b/libisoburn/trunk/xorriso/xorriso_timestamp.h
index a1b43955..728db93e 100644
--- a/libisoburn/trunk/xorriso/xorriso_timestamp.h
+++ b/libisoburn/trunk/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2008.04.01.213121"
+#define Xorriso_timestamP "2008.04.03.204051"
diff --git a/libisoburn/trunk/xorriso/xorrisoburn.c b/libisoburn/trunk/xorriso/xorrisoburn.c
index a490e0d8..2cc49724 100644
--- a/libisoburn/trunk/xorriso/xorrisoburn.c
+++ b/libisoburn/trunk/xorriso/xorrisoburn.c
@@ -959,6 +959,7 @@ int Xorriso_write_session(struct XorrisO *xorriso, int flag)
    Xorriso_msgs_submit(xorriso, 0, xorriso->info_text, 0, "FAILURE", 0);
    {ret= 0; goto ex;}
  }
+ isoburn_igopt_get_effective_lba(sopts, &(xorriso->session_lba));
 
  ret= Xorriso_make_write_options(xorriso, drive, &burn_options, 0);
  if(ret<=0)
@@ -995,10 +996,11 @@ int Xorriso_write_session(struct XorrisO *xorriso, int flag)
    tracks= burn_session_get_tracks(sessions[0], &num_tracks);
    if(tracks!=NULL && num_tracks>0) {
      burn_track_get_counters(tracks[0],&readcounter,&writecounter);
+     xorriso->session_blocks= (int) (writecounter/ (off_t) 2048);
      sprintf(xorriso->info_text,
-             "ISO image produced: %d sectors. Written to media: %d sectors\n",
-             (int) (readcounter/ (off_t) 2048),
-             (int) (writecounter/ (off_t) 2048));
+    "ISO image produced: %d sectors. Written to media: %d sectors at LBA %d\n",
+        (int) (readcounter/ (off_t) 2048),
+        xorriso->session_blocks, xorriso->session_lba);
      Xorriso_info(xorriso, 0);
    }
  }