diff --git a/releng/releng_isocontent b/releng/releng_isocontent
index b41acbba..e5b4d092 100755
--- a/releng/releng_isocontent
+++ b/releng/releng_isocontent
@@ -13,22 +13,20 @@ if [ ! -x $RELENG_XORRISO ]; then
 fi
 
 # check data dir, if any and after checking -x xorriso
-#if [ -d "${GEN_DATA_DIR}" ]; then
-# printf "\n${SELF}: directory %s exists!" ${GEN_DATA_DIR}
-# printf "\n${SELF}: use '${SELF} -c1' to remove.\n"
-# exit 8
-#else
-# mkdir "${GEN_DATA_DIR}"
-#fi
+if [ -d "${GEN_DATA_DIR}" ]; then
+ printf "\n${SELF}: directory %s exists!" ${GEN_DATA_DIR}
+ printf "\n${SELF}: use '${SELF} -c1' to remove.\n"
+ exit 8
+else
+ mkdir "${GEN_DATA_DIR}"
+fi
 
-export prog=${SELF}
 export xorriso=${RELENG_XORRISO}
 export workdir=${GEN_DATA_DIR}
 export image_file="$workdir"/xorriso_hardlinks.iso
 export on_disk="$workdir"/xorriso_hardlinks_test_dir
 export in_iso=""
 export copy_on_disk="$workdir"/xorriso_hardlinks_copy_dir
-export keep=${KEEP}
 export failure=0
 export simulate_failure=${SIMULATE_FAILURE}
 export next_is_xorriso=0
@@ -36,145 +34,18 @@ export next_is_rc=0
 export bad=0
 export report_about="-report_about UPDATE"
 
-#config_by_var() {
-  # This is called once before option interpretation, and once for each
-  # option -rc.
-  # Variables get set to empty content to keep them from being applied
-  # more than once and thus overriding settings of higher precedence.
-
-#  test -n "$RELENG_XORRISO" && xorriso="$RELENG_XORRISO" && RELENG_XORRISO=
-
-#  test -n "$RELENG_WORKIMAGE" && image_file="$RELENG_WORKIMAGE" \
-#                              && RELENG_WORKIMAGE=
-
-#  test -n "$RELENG_WORKDIR" && on_disk="$RELENG_WORKDIR" && RELENG_WORKDIR=
-
-#  test -n "$RELENG_ISODIR" && in_iso="$RELENG_ISODIR" && RELENG_ISODIR=
-
-#  test -n "$RELENG_WORKCOPYDIR" && copy_on_disk="$RELENG_WORKCOPYDIR" \
-#                                && RELENG_WORKCOPYDIR=
-
-#}
-
-#clean_up() {
-#  if test "$keep" = 1
-#  then
-#    echo "=== Kept test area because of option -keep" >&2
-#    echo "$on_disk" "$copy_on_disk" "$image_file" "$workdir" >&2
-#  else
-#    echo "=== Removing test area" >&2
-#    rm -r "$on_disk" "$copy_on_disk" "$image_file"
-#    rm -r "$workdir"
-#  fi
-#}
-
-
-# Setup
-
-
-# Interpret a default configuration file here, if the test has one.
-# This one has none.
-
-# >>> Best would be if the configuration file would not override env variables.
-
-# Process env variables and default configfile variables together
-# config_by_var
-
-
-# Now interpret program arguments and possibly given config files
-#for i in "$@"
-#do
-#  if test "$next_is_xorriso" = 1
-#  then
-#    xorriso="$i"
-#    next_is_xorriso=0
-#  elif test "$next_is_rc" = 1
-#  then
-
-    # >>> This looks darn dangerous. We need a trustworthy config interpreter.
-    # >>> http://www.netjeff.com/humor/item.cgi?file=ShootInFoot-OS
-#    . "$i"
-
-#    config_by_var
-#    next_is_rc=0
-#  elif test x"$i" = x"-rc"
-#  then
-#    next_is_rc=1
-#  elif test x"$i" = x"-keep"
-#  then
-#    keep=1
-#  elif test x"$i" = x"-cleanup"
-#  then
-#    keep=0
-#    cleanup
-#    exit 0
-#  elif test x"$i" = x"-xorriso"
-#  then
-#    next_is_xorriso=1
-#  elif test x"$i" = x"-v"
-#  then
-#    report_about="-report_about ALL"
-#  elif test x"$i" = x"-fail"
-#  then
-#    simulate_failure=1
-#  else
-#    echo "Usage: $0 [-rc FILE] [-keep] [-cleanup] [-fail] [-xorriso PATH] [-v]" >&2
-#    exit 2
-#  fi
-# done
-
 test -z "$in_iso" && in_iso="$on_disk"
 
-if test -d ./releng_generated_data
-then
-  dummy=dummy
-else
-  echo "=== TEST ENVIRONMENT ERROR: $prog : No ./releng_generated_data directory existing" >&2
-  echo "=== Is the current working directory really ./releng of libisoburn ?" >&2
-  echo "FAIL : $prog : Test environment error : No ./releng_generated_data directory"
-  exit 3
-fi
-if test -e "$workdir"
-then
-  echo "=== TEST ENVIRONMENT ERROR: $prog : Existing work directory:" >&2
-  ls -ld "$workdir" >&2
-  bad=1
-fi
-if test -e "$image_file"
-then
-  echo "=== TEST ENVIRONMENT ERROR: $prog : Existing image_file target:" >&2
-  ls -ld "$image_file" >&2
-  bad=1
-fi
-if test -e "$on_disk"
-then
-  echo "=== TEST ENVIRONMENT ERROR: $prog : Existing on_disk target:" >&2
-  ls -ld "$on_disk" >&2
-  bad=1
-fi
-if test -e "$copy_on_disk"
-then
-  echo "=== TEST ENVIRONMENT ERROR: $prog : Existing copy_on_disk target:" >&2
-  ls -ld "$copy_on_disk" >&2
-  bad=1
-fi
-if test "$bad" = 1
-then
-  echo "FAIL : $prog : Test environment error : Existing work files"
-  exit 3
-fi
-
-bad=0
-mkdir "$workdir" || bad=1
+# mkdir "$workdir" || bad=1
 mkdir "$on_disk" || bad=1
 if test "$bad" = 1
 then
-  echo "FAIL : $prog : Test environment error : Cannot make directories"
+  echo -e "\n${SELF}: FAIL : Test environment error : Cannot make directories"
   exit 3
 fi
 
-
-echo "=== Setting up $on_disk with several hardlinks" >&2
+# All must be set at this point
+printf "\n${SELF}: Setting up $on_disk with several hardlinks" >&2
 echo test_content >"$on_disk"/file_1 || exit 1
 echo test_content >"$on_disk"/file_2 || exit 1
 ln "$on_disk"/file_1 "$on_disk"/file_1_link_a || exit 1
@@ -182,31 +53,32 @@ ln "$on_disk"/file_1 "$on_disk"/file_1_link_b || exit 1
 ln "$on_disk"/file_2 "$on_disk"/file_2_link_a || exit 1
 ls -l "$on_disk"/*
 
+# trivial ISO 9660 image validation routine
 is_valid_iso9660() {
  ISOfile="$1"
  if [ ! -f ${ISOfile} ]; then
    failure=1
-   printf "${prog}: FAIL: Not found: ${ISOfile}\n"
+   printf "\n${SELF}: FAIL: Not found: ${ISOfile}\n"
  fi
  if file ${ISOfile} | grep -P "ISO\s+9660\s+CD-ROM\s+filesystem\s+data" >/dev/null 2>&1; then
-   printf "=== Resulting ${ISOfile} OK. Looks like ISO 9660 filesystem.\n"
+   printf "\n${SELF}: Resulting ${ISOfile} OK. Looks like ISO 9660 filesystem.\n"
  else
    failure=1
-   printf "${prog}: FAIL: ${ISOfile} DOES NOT look like ISO 9660 filesystem data.\n"
+   printf "\n${SELF}: FAIL: ${ISOfile} DOES NOT look like ISO 9660 filesystem data.\n"
  fi
 }
 
-echo -e "\n=== Producing simple image via -o" >&2
+echo -e "\n${SELF}: Producing simple image via -o" >&2
 "$xorriso" -as mkisofs "$on_disk" -o      "$workdir"/image_minus_o.iso
 is_valid_iso9660                          "$workdir"/image_minus_o.iso
-echo -e "\n=== Producing simple image via redirect" >&2
+echo -e "\n${SELF}: Producing simple image via redirect" >&2
 "$xorriso" -as mkisofs "$on_disk" >       "$workdir"/image_redirected.iso
 is_valid_iso9660                          "$workdir"/image_redirected.iso
-echo -e "\n=== Producing simple image via pipe" >&2
+echo -e "\n${SELF}: Producing simple image via pipe" >&2
 "$xorriso" -as mkisofs "$on_disk" | cat > "$workdir"/image_piped.iso
 is_valid_iso9660                          "$workdir"/image_piped.iso
 
-echo -e "\n=== Producing simple image - for_backup/update_r/hardlinks" >&2
+echo -e "\n${SELF}: Producing simple image with for_backup/update_r/hardlinks" >&2
 "$xorriso" \
   $report_about \
   -version \
@@ -217,7 +89,7 @@ echo -e "\n=== Producing simple image - for_backup/update_r/hardlinks" >&2
   -hardlinks perform_update
 is_valid_iso9660                         "$image_file"
 
-echo "=== Copying from image to temporary disk tree" >&2
+echo -e "\n${SELF}: Copying from image to temporary disk tree" >&2
 "$xorriso" \
   $report_about \
   -for_backup \
@@ -229,53 +101,49 @@ echo "=== Copying from image to temporary disk tree" >&2
 
 if test "$simulate_failure" = 1
 then
-  echo "===" >&2
-  echo "=== SIMULATING FAILURE BY REMOVING AN EXTRACTED FILE" >&2
-  echo "===" >&2
-  echo "FAIL : $prog : Simulated failure caused by option -fail"
+  echo -e "\n${SELF}: SIMULATING FAILURE BY REMOVING AN EXTRACTED FILE" >&2
+  echo -e "\n${SELF}: FAIL : Simulated failure caused by option -fail"
   rm "$copy_on_disk"/file_1_link_b
 fi
 
 
-echo "=== Comparing original disk tree and temporary one" >&2
+printf "\n${SELF}: Comparing original disk tree and temporary one..." >&2
 diff -r "$on_disk" "$copy_on_disk"
 if test "$?" -ne 0
 then
-  echo "=== WRONG: diff -r $on_disk $copy_on_disk   reports differences" >&2
-  echo "FAIL : $prog : diff -r reports differences"
+  echo -e "\n${SELF}: FAIL : diff -r $on_disk $copy_on_disk   reports differences" >&2
+  echo -e "\n${SELF}: FAIL : diff -r reports differences"
   failure=1
 else
-  echo "=== OK" >&2
+  printf "OK" >&2
 fi
 
-echo "=== Checking for hardlinks being siblings" >&2
+printf "\n${SELF}: Checking for hardlinks being siblings...\n"
 ls -l "$copy_on_disk"/*
 x=$(echo $(ls -l "$copy_on_disk"/* | awk '{print $2}'))
 expected="3 3 3 2 2"
 if test x"$x" = x"$expected"
 then
-  echo "=== OK" >&2
+  printf "\n${SELF}: Checking for hardlinks being siblings. Done. OK.\n" >&2
 else
-  echo "=== WRONG: Link count of extracted files is not as expected." >&2
-  echo "=== Expected:  $expected" >&2
-  echo "=== Got     :  $x" >&2
-  echo "FAIL : $prog : Link count of extracted files is not as expected."
+  printf "\n${SELF}: FAIL : Link count of extracted files is not as expected." >&2
+  printf "\n${SELF}: Expected:  $expected" >&2
+  printf "\n${SELF}: Got     :  $x\n" >&2
   failure=1
 fi
 
-
+#
 cleanup
 
-
 # Report result
 echo 
 if test "$failure" = 1
 then
-  echo "======== $prog :" 'FAILED'
+  printf "${SELF}: FAILED"
   echo 
   exit 1
 else
-  echo "======== $prog :" "Passed"
+  printf "${SELF}: Passed"
   echo 
 fi