diff --git a/mqtt-grep-color b/mqtt-grep-color
index ce8ad77..25c2faf 100644
--- a/mqtt-grep-color
+++ b/mqtt-grep-color
@@ -30,17 +30,19 @@ then
     # I'm on BusyBox
     ### grepexp="^ *$|[\}{ ]|\[\]|\[\{|\}\]" # { must be escaped
     # colorizes  }{, etc. if no other grep expression given; space must be there!
-    [ "$stdbufcmd_tr" ] || echo "$scriptname: Warning: Install stdbuf for better line buffering! (Package coreutils-stdbuf on OpenWrt)" 1>&2
+    [ "$stdbufcmd_tr" ] || cEchoErr "Warning: Install stdbuf for better line buffering! (Package coreutils-stdbuf on OpenWrt)"
 else
     # Not on BusyBox
     ### grepexp="^ *$|[\}{ ]|\[\]|\[{|\}\]"  # { must NOT be escaped
     # grepexp="$grepexp| PNG"
     GREPOPTS="--text --color=always --line-buffered"
-    [ "$stdbufcmd_tr" ] || echo "$scriptname: Warning: Install stdbuf for better line buffering!" 1>&2
+    [ "$stdbufcmd_tr" ] || cEchoErr "Warning: Install stdbuf for better line buffering!"
 fi
 
-command -v mosquitto_sub > /dev/null || { echo "$0: Error: Install mosquitto_sub first, e.g. from package mosquitto-client-nossl" 1>&2 ; exit 1 ;  }
-command -v gawk > /dev/null || { echo "$0: Error: Install gawk first, e.g. from package gawk" 1>&2 ; exit 1 ;  }
+cCmv()	{ command -v "$@" > /dev/null ; } # find out whether a command exists
+
+cCmv mosquitto_sub || { cEchoErr "Error: Install mosquitto_sub first, e.g. from package mosquitto-client-nossl" ; exit 1 ;  }
+cCmv gawk          || { cEchoErr "Error: Install gawk first, e.g. from package gawk" ; exit 1 ;  }
 
 mqtthost=""
 noretained="-v"   # use "-v" to make sure $noretained is not an empty option
@@ -52,18 +54,15 @@ awkDeltaTime=0            # default
 scriptname="${0##*/}"
 jsonppcmd="cat"
 
-remove_unwanted_chars() {
-     tr -d '()"^%$ \r\000-\011\013-\037'
-}
-
-cCmv()	{ command -v "$@" >$fNul ;} # find out whether a command exists
+cRemoveUnwantedChars() {  tr -d ')("^%$ \r\000-\011\013-\037' ; }
+cEchoErr() { echo "$scriptname: $*" 1>&2 ; }
 
 ### process command line options ###
 
-while getopts "?e:h:t:T:f:p:W:Rl:C:SrsconPxv-" opt
+while getopts "?e:h:t:T:f:p:W:RDl:C:SrsconPxv-" opt
 do
     case "$opt" in
-    \?) echo "Usage: $scriptname -e expr -h host -x -v -t topic1 -t topic2 -o -C maxcnt -p port -P  --  othermosquittoopts" 1>&2
+    \?) cEchoErr "Usage: $scriptname -e expr -h host -x -v -t topic1 -t topic2 -o -C maxcnt -p port -P  --  othermosquittoopts"
         exit 1
         ;;
     e)  grepexp="$OPTARG"
@@ -77,14 +76,17 @@ do
             hivemq)         mqtthost="broker.hivemq.com"  ;;
             emqx)	        mqtthost="broker.emqx.io"   ;;
     		dash)           mqtthost="broker.mqttdashboard.com"    ;; # https://moxd.io/2015/10/17/public-mqtt-brokers/
-            *)              mqtthost="$( echo "$OPTARG" | remove_unwanted_chars )" ;; # clean up for sec purposes
+            *)              mqtthost="$( echo "$OPTARG" | cRemoveUnwantedChars )" ;; # clean up for sec purposes
 		esac
         [ "$bVerbose" ] && { host $mqtthost || nslookup $mqtthost ; ping -4 -c 1 $mqtthost ; ping -6 -c 1 $mqtthost ; }
         # ... used for checking: for h in test eclipse iot mosca hivemq emqx dash ; do echo ==== $h ==== ; mqtt-grep-color -W 3 -C 1 -v -h $h ; done
         ;;
-    t)  topics="$topics -t $( echo "$OPTARG" | sed -e 's:/$:/\#:' )" # as a service, add \# to any trailing /
-        ;;
-    T)  topics="$topics -T $( echo "$OPTARG" | sed -e 's:/$:/\#:' )"
+    t|T)  if [ "$OPTARG" != "${OPTARG%/}" ] ; then # implicitly add the MQTT wildcard hashtag to any trailing "/"           
+            topics="$topics -$opt $OPTARG#"    # topics="$topics -t $( echo "$t" | sed -e 's:/$:/\#:' )"
+        else
+            [ ! "$OPTARG" != "${OPTARG%#}" ] && cEchoErr "Warning: Option -$opt \"$OPTARG\" has no trailing / or \#, i.e. is not a wildcard topic"
+            topics="$topics -$opt $OPTARG"
+        fi
         ;;
     f)  inputfile="$OPTARG"
         ;;
@@ -94,45 +96,45 @@ do
         ;;
     R)  noretained="-R"
         ;;
-    l)  awkMinTopicChars="$( echo "$OPTARG" | remove_unwanted_chars )" # minimum length of outputted topic string (padded with spaces)
+    D)  bRemoveRetained=1 # will continue with streaming after removing the retained messages...
         ;;
-    C)  maxcount="-C $( echo "$OPTARG" | remove_unwanted_chars )" # clean up for sec purposes
+    l)  awkMinTopicChars="$( echo "$OPTARG" | cRemoveUnwantedChars )" # minimum length of outputted topic string (padded with spaces)
+        ;;
+    C)  maxcount="-C $( echo "$OPTARG" | cRemoveUnwantedChars )" # clean up for sec purposes
         ;;
     n)  noColor="1"
         ;;
-    c)  awkAdditionalSkipLines="1"
+    c)  awkAdditionalSkipLines=1
         ;;
-    P)  if command -v json_pp ; then
-            jsonppcmd=json_pp
-        else
-            echo "$scriptname: Warning: json_pp not found..." 1>&2
-        fi
+    P)  cCmv json_pp && jsonppcmd=json_pp || cEchoErr "Warning: json_pp not found..."
         ;;
-    r)  awkRemoveKeyQuotes="1"
+    r)  awkRemoveKeyQuotes=1
         ;;
-    s)  sSuppressAttrs="$sSuppressAttrs $( echo "$OPTARG" | tr -d -c "A-Za-z0-9_")" # attrs that will be tried to be eliminated
+    s)  sSuppressAttrs="$sSuppressAttrs $( echo "$OPTARG" | tr -d -c "A-Za-z0-9_")" # JSON attrs that will be tried to be eliminated
         ;;
     S)  awkTimeFormat="%s"
         awkTimeLen=3 # only the last three digits (len of %s is 11)
         awkDeltaTime=1
         ;;
-    o)  awkOptimizeJSON="1"
+    o)  awkOptimizeJSON=1
         ;;
     x)  set -x # turn on shell debugging from here on
         ;;
     v)  bVerbose="yes" # still unused...
         ;;
-    -)  echo "-- not supported."
-        exit 1
+    -)  echo "option -$opt not supported. Exiting." ; exit 1
         ;;
     esac
 done
 
 shift "$((OPTIND-1))"   # Discard options processed by getopts, any remaining options will be passed to mosquitto_sub
 
-[ -z "$topics" ] && topics="-t #"         # use '#' as MQTT topic if nothing else given
+if [ -z "$topics" ] ; then
+    [ "$bRemoveRetained" ] && { cEchoErr "Retained topics to be removed must be given explicitly with option -t. Exiting." ; exit 1 ; }
+    topics="-t #"         # use '#' as default MQTT topic if nothing else given
+fi
 
-# These are the following steps for processing the MQTT stream:
+# These are the basic steps for processing the MQTT stream:
 # 1. remove any non-printable stuff from the data,
 # 2. color the MQTT topic red,
 # 3. put the time in front and color it yellow,
@@ -144,7 +146,9 @@ if [ -n "$inputfile" ] ; then
     cat "$inputfile"
 else
     _ms_options="${mqtthost:+-h $mqtthost} ${port:+-p $port} -v $topics $noretained $maxcount $messageTimeOut $*"
-    [ "$bVerbose" ] && echo "$scriptname: m_s options: $_ms_options" 1>&2
+    [ "$bRemoveRetained" ] && mosquitto_sub $_ms_options -W 1 --retained-only --remove-retained 2>&1 | 
+       awk -v topics="$topics" '/^Timed out/ { next } { count++ ; print } BEGIN { print "=== Removing retained messages with topics: " topics " ===" ; count=0 } END { print "=== Removed " count " retained messages. ===" }' # grep -v "^Timed out$"
+    [ "$bVerbose" ] && cEchoErr "mosquitto_sub options: $_ms_options"
     mosquitto_sub $_ms_options
 fi |
 gawk -b -v timeLen="$awkTimeLen" -v timeFormat="$awkTimeFormat" -v deltaTime="$awkDeltaTime" -v verbose="$bVerbose" -v removeKeyQuotes="$awkRemoveKeyQuotes" \