diff --git a/bin/runtime.cmd b/bin/runtime.cmd
index 6b1a49d3..3c226f7e 100644
--- a/bin/runtime.cmd
+++ b/bin/runtime.cmd
@@ -512,10 +512,10 @@ if {[::punk::multishell::is_main]} {
 # -- --- --- --- --- --- --- --- --- --- --- --- --- ---end Tcl Payload
 # end hide from unix shells \
 HEREDOC1B_HIDE_FROM_BASH_AND_SH
-# csh/tcsh/sh/bash use oldschool backticks and sed lowest common denominator \
-echo "script: `echo $0 | sed 's/^-//'`"
-# csh/tcsh/sh/bash use oldschool backticks and sed lowest common denominator \
-echo "shell: " `ps -p $$ | awk '$1 != "PID" {print $(NF)}' | tr -d '()' | sed -E 's/^.*\/|^-//'`
+#Be wary of any non-trivial sed/awk etc - can be brittle to maintain across linux,freebsd,macosx due to differing implementations
+#echo "script: `echo $0 | sed 's/^-//'`"
+# csh/tcsh/sh/bash use oldschool backticks and sed - lowest common denominator \
+#echo "shell: " `ps -p $$ | awk '$1 != "PID" {print $(NF)}' | tr -d '()' | sed -E 's/^.*\/|^-//'`
 #csh/tcsh diversion \
 test "$argv[*]" != "[*]" && ( /usr/bin/env bash $argv[*]; exit )
 #other non-bash diversion \
@@ -525,7 +525,7 @@ test `ps -p $$ | awk '$1 != "PID" {print $(NF)}' | tr -d '()' | sed -E 's/^.*\/|
 # sh/bash \
 shift && set -- "${@:1:$#-1}"
 
-#echo "shell:" `ps -o args= $$ | sed -E 's/^.*\/|^-//' | awk '{print $1}'`
+echo "shell:" `ps -o args= $$ | sed -E 's/^.*\/|^-//' | awk '{print $1}'`
 #------------------------------------------------------
 # -- This if block only needed if Tcl didn't exit or return above.
 if false==false # else {
@@ -568,28 +568,49 @@ else
     #os="$OSTYPE"
     os="other"
 fi
-echo ostype: $OSTYPE
-shellconfigline=$( sed -n "/: <<nextshell_start>>/{:a;n;/: <<nextshell_end>>/q;p;ba}" "$0" | grep $os)
-#echo $shellconfigline;
-if [[ $shellconfigline == *"nextshelltype"* ]]; then
-    echo "found config for os $os"
-    split1="${shellconfigline#*=}"  #remove everything through the first '='
-    #echo "split1: $split1"
-    pathraw="${split1%%\"*}" #take everything before the quote - use %% to get longest match
-    pathraw="${pathraw//\"/}"  #remove quote
-    nextshellpath="${pathraw/%_*/}"  #remove trailing underscores (% = must match at end)
-    #echo "nextshellpath: $nextshellpath"
-    split2="${split1#*=}"
-    #echo "split2: $split2"
-    split2="${split2//\"/}"
-    nextshelltype="${split2/%_*/}"
-    echo "nextshelltype: $nextshelltype"
-else
-    echo "unable to find config for os $os"
-    echo "shellconfigline: $shellconfigline"
-    nextshellpath=""
-    nextshelltype=""
-fi
+#echo ostype: $OSTYPE
+## This is the sort of sed that will not work across implementations
+## shellconfiglines=$( sed -n "/: <<nextshell_start>>/{:a;n;/: <<nextshell_end>>/q;p;ba}" "$0" | grep $os)
+#awk tested on linux & freebsd
+shellconfiglines=$( awk '/^:.*<<nextshell_start>>.*$/,/^:.*<<nextshell_end>>.*$/' "$0" | grep $os)
+#echo $shellconfiglines;
+readarray -t arr_oslines <<<"$shellconfiglines"
+nextshellpath=""
+nextshelltype=""
+for ln in "${arr_oslines[@]}"; do
+    if [[ "$ln" == *"nextshellpath"* ]]; then
+        splitln="${ln#*=}"  #remove everything through the first '='
+        pathraw="${splitln%%\"*}" #take everything before the quote - use %% to get longest match
+        #remove trailing underscores (% means must match at end)
+        nextshellpath="${pathraw/%_*/}"  
+        echo "nextshellpath: $nextshellpath"
+    elif [[ "$ln" == *"nextshelltype"* ]]; then
+        splitln="${ln#*=}"
+        typeraw="${splitln%%\"*}"
+        nextshelltype="${typeraw/%_*/}"
+    fi
+done
+
+#if [[ $shellconfigline == *"nextshelltype"* ]]; then
+#    #echo "found config for os $os"
+#    split1="${shellconfigline#*=}"  #remove everything through the first '='
+#    #echo "split1: $split1"
+#    pathraw="${split1%%\"*}" #take everything before the quote - use %% to get longest match
+#    pathraw="${pathraw//\"/}"  #remove quote
+#    nextshellpath="${pathraw/%_*/}"  #remove trailing underscores (% = must match at end)
+#    #echo "nextshellpath: $nextshellpath"
+#    split2="${split1#*=}"
+#    #echo "split2: $split2"
+#    split2="${split2//\"/}"
+#    nextshelltype="${split2/%_*/}"
+#    echo "nextshelltype: $nextshelltype"
+#else
+#    echo "unable to find config for os $os"
+#    echo "shellconfigline: $shellconfigline"
+#    nextshellpath=""
+#    nextshelltype=""
+#fi
+
 exitcode=0
 #-- sh/bash launches nextscript here instead of shebang line at top
 if [[ "$nextshelltype" != "bash" && "$nextshelltype" != "none" ]]; then 
@@ -863,12 +884,14 @@ function GetDynamicParamDictionary {
         return $DynParamDictionary
     }
 }
+# Example usage:
 # GetDynamicParamDictionary 
 # - This can make it easier to share a single set of param definitions between functions
 # - sample usage
 #function ParameterDefinitions {
 #    param(
-#        [Parameter(Mandatory)][string] $myargument
+#        [Parameter(Mandatory)][string] $myargument,
+#        [Parameter(ValueFromRemainingArguments)] $opts
 #    )
 #}
 #function psmain {
@@ -879,10 +902,15 @@ function GetDynamicParamDictionary {
 #       #called once with $PSBoundParameters dictionary
 #       #can be used to validate arguments, or set a simpler variable name for access
 #       switch ($PSBoundParameters.keys) {
-#           'myargumentname' { 
+#           'myargument' { 
 #               Set-Variable -Name $_ -Value $PSBoundParameters."$_"
 #           }
-#           #...
+#           'opts' {
+#               write-warning "Unused parameters: $($PSBoundParameters.$_)" 
+#           }
+#           Default {
+#               write-warning "Unhandled parameter -> [$($_)]"
+#           }
 #       }
 #       foreach ($boundparam in $PSBoundParameters.GetEnumerator()) {
 #           #...
@@ -890,7 +918,7 @@ function GetDynamicParamDictionary {
 #   }
 #   end {
 #       #Main function logic
-#       Write-Host "myargumentname value is: $myargumentname"
+#       Write-Host "myargument value is: $myargument"
 #       #myotherfunction @PSBoundParameters
 #   }
 #}