make _round_float more LANG independent (C not installed)

bashbot.sh

@@ -30,7 +30,7 @@ BOTCOMMANDS="-h  help  init  start  stop  status  suspendback  resumeback  killb
 #     8 - curl/wget missing
 #     10 - not bash!
 #
-#### $$VERSION$$ v1.30-0-g3266427
+#### $$VERSION$$ v1.31-dev-0-gad532cc
 ##################################################################
 
 # emmbeded system may claim bash but it is not
@@ -89,7 +89,8 @@ _is_function() {
 # if $2 is not given or is not a positive number zero is assumed
 _round_float() {
 	local digit="$2"; [[ "$2" =~ ^[${o9o9o9}]+$ ]] || digit="0"
-	{ LC_ALL=C.utf-8 printf "%.${digit}f" "$1"; } 2>/dev/null
+	: "$(LC_ALL=C printf "%.${digit}f" "$1" 2>/dev/null)"
+	printf "%s" "${_//,/.}" # make more LANG independent
 }
 # date is external, printf is much faster
 _date(){

doc/7_develop.md

@@ -284,8 +284,9 @@ bar="${_/__x/_c}"	# a_b_c
 : ${SOMEVAR}		# "String in var" $_ -> "var" 
 : $(<"file")		# "Content     of\n  file" $_ -> "file"
 
-# pitfall test command
-[ -n "$MYVAR" ] && echo "$_"	# outputs "]" 
+# pitfall [ vs. test command
+[ -n "xxx" ] && echo "$_"	# $_ -> "]" 
+test -n "xxx" && echo "$_"	# $_ -> "xxx" 
 
 # pitfall command substitution: globbing and IFS is applied!
 : "$(echo "a* is born")"# $_ -> a* is globbed even quoted!
@@ -386,5 +387,5 @@ fi
 
 #### [Prev Function Reference](6_reference.md)
 
-#### $$VERSION$$ v1.30-0-g3266427
+#### $$VERSION$$ v1.31-dev-0-gad532cc