diff --git a/releng/README b/releng/README
index 100410c7..606e66c1 100644
--- a/releng/README
+++ b/releng/README
@@ -79,6 +79,7 @@ There are several options which work with run_all_auto and any single test.
   -k  keep self-generated data.
   -c  cleanup temporary data kept from previous run and exit.
   -f  simulate failure.
+  -h  print this help text
   --  end of general options, begin of test specific options.
 After option "--", there may be given options which are specific to
 particular manually executable test scripts. 
@@ -109,12 +110,15 @@ the user or require sysadmin considerations before they are run:
   If no option --dev is given, then the user gets asked which of the listed
   drives to examine more closely.
 
->>> ./manual_burn -x ../xorriso/xorriso [-- [--dev device_file_to_use]
->>>                                         [--what ...directory...]]
->>> burns the content of the directory given with --what onto re-usable
->>> media: CD-RW, DVD-RW, DVD-RAM, DVD+RW, BD-RE.
->>> Other media types get refused.
->>> Data, which are possibly present on the media, get overwritten.
+./manual_burn -x ../xorriso/xorriso [-- [--dev device_file_to_use]
+                                        [--what ...directory...] [--any_media]]
+  Burns the content of the directory given with --what onto re-usable
+  media: CD-RW, DVD-RW, DVD-RAM, DVD+RW, BD-RE.
+  Other media types get refused, unless option --any_media is given.
+  Data, which are possibly present on the media, get overwritten.
+  The result gets check read and compared with the state of the input
+  directory. MD5 mismatch causes a test failure. Differences to the directory
+  state are reported but still regarded as success.
 
 >>> ./run_all_manual
 
@@ -165,6 +169,8 @@ Predefined are:
   30 = Unexpected state of own directory for self generated files
   29 = Not in ./releng directory or missing essential parts of ./releng
 
+When exiting prematurely, make sure to call function cleanup.
+
 
                  General options, variables, and functions
 
@@ -230,3 +236,6 @@ TODO:
 
 * derive a GNU xorriso test suite from libisoburn test suite
 
+* auto_ tests should know whether they work underneath run_all_auto
+  or whether they run standalone
+
diff --git a/releng/manual_burn b/releng/manual_burn
index 3740379d..81e416be 100755
--- a/releng/manual_burn
+++ b/releng/manual_burn
@@ -19,7 +19,7 @@ Specific options:
                    to existing regular files.
 Overview:
        Test burning to re-usable media CD-RW, DVD-RW, DVD-RAM, DVD+RW, BD-RE.
-       One time usable media will be rejected deliberately.
+       By default, one-time usable media will be rejected deliberately.
 HLP
 }
 
@@ -102,7 +102,7 @@ if test -e "$dev"
 then
   if test "$any_media" = 1 -a -f "$dev"
   then
-    echo "FAIL: --dev $dev leads to an existing regular file"
+    echo "FAIL: ${SELF} : --dev $dev leads to an existing regular file"
     echo
     cleanup
     exit 31
@@ -110,7 +110,7 @@ then
 else
   if test "$any_media" = "0"
   then
-    echo "FAIL: --dev $dev does not lead to an existing file"
+    echo "FAIL: ${SELF} : --dev $dev does not lead to an existing file"
     echo
     cleanup
     exit 31
@@ -125,7 +125,7 @@ set -e
 if test "$ret" -ne 0
 then
   echo "$res" >&2
-  echo "FAIL: Non-zero exit value $ret with: $RELENG_XORRISO -outdev $dev"
+  echo "FAIL: ${SELF} : Non-zero exit value $ret with: $RELENG_XORRISO -outdev $dev"
   echo
   cleanup
   exit 1
@@ -141,7 +141,7 @@ then
     echo "Recognized as re-usable."
   elif test "$media" = "is not recognizable"
   then
-    echo "FAIL: No recognizable media detected in: '$dev'"
+    echo "FAIL: ${SELF} : No recognizable media detected in: '$dev'"
     echo
     cleanup
     exit 2
@@ -149,7 +149,7 @@ then
   then
     echo "Accepted media only because of option --any_media : '$media'"
   else
-    echo "FAIL: No re-usable media detected, but: '$media'"
+    echo "FAIL: ${SELF} : No re-usable media detected, but: '$media'"
     echo
     cleanup
     exit 2
@@ -168,17 +168,25 @@ ret=$?
 set -e
 if test "$ret" -ne 0
 then
-  echo "FAIL: Non-zero exit value with burn run: $ret"
+  echo "FAIL: ${SELF} : Non-zero exit value with burn run: $ret"
   echo
   cleanup
   exit 1
 fi
 
-# >>> simulate failure
-# >>> if test -f "$dev"
-# >>> then
-# >>>   ... alter image ... 
-# >>> fi
+if test "$SIMULATE_FAILURE" = 1
+then
+  echo "FAIL: ${SELF} : Simulated failure caused by option -f" 
+  if test -f "$dev"
+  then
+    # Alter image 
+    dd if=/dev/urandom bs=2K count=1 \
+       of="$dev" conv=notrunc seek=400
+  else
+    cleanup
+    exit 1
+  fi
+fi
 
 # Check read
 echo "$RELENG_XORRISO" -for_backup -indev "$dev" \
@@ -194,7 +202,7 @@ ret=$?
 set -e
 if test "$ret" -ne 0
 then
-  echo "FAIL: Non-zero exit value with checkread run: $ret"
+  echo "FAIL: ${SELF} : Non-zero exit value with checkread run: $ret"
   echo
   cleanup
   exit 1