diff --git a/xorriso/xorriso.1 b/xorriso/xorriso.1
index e8d561e8..35315d5c 100644
--- a/xorriso/xorriso.1
+++ b/xorriso/xorriso.1
@@ -1325,6 +1325,12 @@ exist in the ISO image.
 E.g.
 .br
   -find /home/thomas -exec add_missing /thomas_on_cd
+.br
+"is_full_in_iso" iso_rr_path_start reports if the counterpart in the ISO image
+contains files. To be used with -type "m" to report mount points.
+.br
+"empty_iso_dir" iso_rr_path_start deletes all files from the counterpart
+in the ISO image. To be used with -type "m" to truncate mount points.
 .TP
 \fB\-compare\fR disk_path iso_rr_path
 Compare attributes and eventual data file content of a fileobject in the
diff --git a/xorriso/xorriso.c b/xorriso/xorriso.c
index 838a4b16..29c8580b 100644
--- a/xorriso/xorriso.c
+++ b/xorriso/xorriso.c
@@ -2405,7 +2405,8 @@ struct FindjoB {
    16= not_in_iso
    17= update
    18= add_missing
->>>19= empty_iso_dir
+   19= empty_iso_dir
+   20= is_full_in_iso
  */
  int action;
  char *target;
@@ -6143,7 +6144,7 @@ int Xorriso_findx_action(struct XorrisO *xorriso, struct FindjoB *job,
    action= 0;
  if(action<0)
    action= 0;
- if(action==15 || action==16 || action==18 || action==19) {
+ if(action==15 || action==16 || action==18 || action==19 || action==20) {
    /* in_iso , not_in_iso, add_missing */
    Findjob_get_start_path(job, &disk_prefix, 0);
    if(strncmp(abs_path, disk_prefix, strlen(disk_prefix))!=0)
@@ -6197,6 +6198,23 @@ int Xorriso_findx_action(struct XorrisO *xorriso, struct FindjoB *job,
              Text_shellsafe(iso_path, sfe, 0));
      Xorriso_msgs_submit(xorriso, 0, xorriso->info_text, 0, "UPDATE", 0);
    }
+ } else if(action==20) { /* is_full_in_iso */
+   ret= Xorriso_iso_lstat(xorriso, iso_path, &stbuf, 0);
+   if(ret==-1)
+     return(1);
+   if(!S_ISDIR(stbuf.st_mode))
+     return(1);
+   strcpy(sfe, xorriso->wdi);
+   strcpy(xorriso->wdi, iso_path);
+   ret= Xorriso_ls(xorriso, 4|8);
+   strcpy(xorriso->wdi, sfe);
+   if(ret>0) {
+     sprintf(xorriso->result_line,
+            "d %s (ISO) : non-empty directory (would not match mount point)\n",
+            Text_shellsafe(iso_path, sfe, 0));
+     Xorriso_result(xorriso,0);
+   }
+   return(1);
  } else {
    sprintf(xorriso->result_line, "%s\n", Text_shellsafe(show_path, sfe, 0));
    Xorriso_result(xorriso, 0);
@@ -7925,7 +7943,7 @@ int Xorriso_option_compare(struct XorrisO *xorriso, char *disk_path,
 {
  int ret, mem_pci, zero= 0, result, follow_links;
  double mem_lut= 0.0;
- char *ipth, *argv[4];
+ char *ipth, *argv[6];
 
  ipth= iso_path;
  if(ipth[0]==0)
@@ -7953,6 +7971,16 @@ int Xorriso_option_compare(struct XorrisO *xorriso, char *disk_path,
      argv[3]= ipth;
      zero= 0;
      ret= Xorriso_option_find(xorriso, 4, argv, &zero, 1|2); /* -findx */
+     if(ret>0 && !xorriso->do_follow_mount) {
+       argv[0]= disk_path;
+       argv[1]= "-type";
+       argv[2]= "m";
+       argv[3]= "-exec";
+       argv[4]= "is_full_in_iso";
+       argv[5]= ipth;
+       zero= 0;
+       ret= Xorriso_option_find(xorriso, 6, argv, &zero, 1|2); /* -findx */
+     }
      if(ret>0)
        ret= xorriso->find_compare_result;
      else
@@ -8561,7 +8589,8 @@ not_enough_arguments:;
      } else if(strcmp(cpt, "in_iso")==0 ||
                strcmp(cpt, "not_in_iso")==0 ||
                strcmp(cpt, "add_missing")==0 ||
-               strcmp(cpt, "empty_iso_dir")==0) {
+               strcmp(cpt, "empty_iso_dir")==0 ||
+               strcmp(cpt, "is_full_in_iso")==0) {
        if(i+1>=end_idx)
          goto not_enough_arguments;
        i++;
@@ -8575,6 +8604,8 @@ not_enough_arguments:;
          action= 18;
        else if(strcmp(cpt, "empty_iso_dir")==0)
          action= 19;
+       else if(strcmp(cpt, "is_full_in_iso")==0)
+         action= 20;
        else
          action= 16;
        Findjob_set_action_target(job, action, other_path_start, 0);
@@ -10046,7 +10077,7 @@ int Xorriso_option_update(struct XorrisO *xorriso, char *disk_path,
 {
  int ret, mem_pci, zero= 0, result, uret, follow_links;
  double mem_lut= 0.0, start_time;
- char *ipth, *argv[4];
+ char *ipth, *argv[6];
  struct stat stbuf;
 
  start_time= Sfile_microtime(0);
@@ -10083,6 +10114,16 @@ int Xorriso_option_update(struct XorrisO *xorriso, char *disk_path,
        argv[3]= ipth;
        zero= 0;
        ret= Xorriso_option_find(xorriso, 4, argv, &zero, 1|2); /* -findx */
+       if(ret>0 && !xorriso->do_follow_mount) {
+         argv[0]= disk_path;
+         argv[1]= "-type";
+         argv[2]= "m";
+         argv[3]= "-exec";
+         argv[4]= "empty_iso_dir";
+         argv[5]= ipth;
+         zero= 0;
+         ret= Xorriso_option_find(xorriso, 6, argv, &zero, 1|2); /* -findx */
+       }
        if(ret>0)
          ret= xorriso->find_compare_result;
        else
diff --git a/xorriso/xorriso_timestamp.h b/xorriso/xorriso_timestamp.h
index 545895cb..245cf3a2 100644
--- a/xorriso/xorriso_timestamp.h
+++ b/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2008.03.07.182411"
+#define Xorriso_timestamP "2008.03.07.220442"
diff --git a/xorriso/xorrisoburn.c b/xorriso/xorrisoburn.c
index 96114593..92f34694 100644
--- a/xorriso/xorrisoburn.c
+++ b/xorriso/xorrisoburn.c
@@ -3414,6 +3414,7 @@ int Xorriso_ls_filev(struct XorrisO *xorriso, char *wd,
    @param flag bit0= long format
                bit1= only check for directory existence
                bit2= do not apply search pattern but accept any file
+               bit3= just count nodes and return number
 */
 int Xorriso_ls(struct XorrisO *xorriso, int flag)
 {
@@ -3468,7 +3469,8 @@ cannot_create_iter:;
  iso_dir_iter_free(iter);
  iter= NULL;
  Xorriso_process_msg_queues(xorriso,0);
-
+ if(flag&8)
+   {ret= filec; goto ex;}
  sprintf(xorriso->info_text, "Valid ISO nodes found: %d\n", filec);
  Xorriso_info(xorriso,1);
 
@@ -3530,7 +3532,7 @@ ex:;
  Xorriso_process_msg_queues(xorriso,0);
  if(node_array!=NULL)
    free((char *) node_array);
- return(1);
+ return(ret);
 }
 
 /* @param boss_iter Opaque handle to be forwarded to actions in ISO image
diff --git a/xorriso/xorrisoburn.h b/xorriso/xorrisoburn.h
index f9f0fc42..7ce4aa56 100644
--- a/xorriso/xorrisoburn.h
+++ b/xorriso/xorrisoburn.h
@@ -94,6 +94,7 @@ int Xorriso_ls_filev(struct XorrisO *xorriso, char *wd,
    @param flag bit0= long format
                bit1= only check for directory existence
                bit2= do not apply search pattern but accept any file
+               bit3= just count nodes and return number
 */
 int Xorriso_ls(struct XorrisO *xorriso, int flag);