diff --git a/VERSION b/VERSION
new file mode 100644
index 0000000..d33c3a2
--- /dev/null
+++ b/VERSION
@@ -0,0 +1 @@
+0.12.0
\ No newline at end of file
diff --git a/tests/test-all.sh b/tests/test-all.sh
index 6c5d74c..aa492e3 100755
--- a/tests/test-all.sh
+++ b/tests/test-all.sh
@@ -2,19 +2,38 @@
 #
 #
 #
+BG=${BG:-0}
+
+run_tests_in_background(){
+	./test-html-base.sh &
+	./test-xml-ns-01.sh &
+	./test-xml-ns-02.sh &
+	./test-xml-ns-03.sh &
+	./test-xml-ns-no-default.sh &	
+}
 
 sep="\n-------------------------------------------------------------\n"
 
 echo
 
-./test-html-base.sh
-echo -e "$sep"
-./test-xml-ns-01.sh
-echo -e "$sep"
-./test-xml-ns-02.sh
-
-echo -e "$sep"
-./test-xml-ns-03.sh
-
-echo -e "$sep"
-./test-xml-ns-no-default.sh
+if [ "$BG" -eq 1 ];then
+	# sorting stdout by PID keeps test description and results more or less ordered but it's not perfect.
+	# To get a clean output run tests without BG=1. Added at issue #15.
+	for i in 1 2 3;do
+		# BG=1 ./test-all.sh
+		run_tests_in_background
+	done | sort -k1,2r
+	
+else
+	./test-html-base.sh
+	echo -e "$sep"
+	./test-xml-ns-01.sh
+	echo -e "$sep"
+	./test-xml-ns-02.sh
+	
+	echo -e "$sep"
+	./test-xml-ns-03.sh
+	
+	echo -e "$sep"
+	./test-xml-ns-no-default.sh
+fi
diff --git a/tests/test-html-base.sh b/tests/test-html-base.sh
index 9bc8b86..ff8af10 100755
--- a/tests/test-html-base.sh
+++ b/tests/test-html-base.sh
@@ -20,7 +20,7 @@ TC05="HTML absolute paths with duplicates (-a -r)"
 TC06="HTML relative paths (-s) containing axes expression axes::elem"
 # TODO: invalid html 
 
-echo "*** HTML tests ($script_name) ***"
+echo_with_pid "Test Suite *** HTML tests ($script_name) ***"
 test_run "TC01"
 test_result "$?"
 
diff --git a/tests/test-lib-src.sh b/tests/test-lib-src.sh
index d95cd03..18eac69 100644
--- a/tests/test-lib-src.sh
+++ b/tests/test-lib-src.sh
@@ -5,7 +5,11 @@ DBG=0
 
 TRACE_FILE='/dev/null'
 [[ -n "$trace" && "$trace" != '/dev/null' ]] && TRACE_FILE="$trace" ;
- 
+
+echo_with_pid(){
+	printf "[%d] %b\n" "$$" "$@"
+}
+
 #---------------------------------------------------------------------------------------
 # Verify test case result and return result and description
 #---------------------------------------------------------------------------------------
@@ -16,16 +20,16 @@ function test_result(){
     tc_result="FAILED"
     if [ "$1" -eq "$retval" ]; then
         tc_result="PASSED"
-        echo "${tc_result}"
+        echo_with_pid "${tc_result}"
     else
-        echo "${tc_result}" | show_color
+        echo_with_pid "${tc_result}" | show_color
     fi
     
 }
 
 function show_color(){
     while read -r line; do 
-        echo -e "  \e[01;31m$line\e[0m" >&2
+        echo -e "\e[01;31m$line\e[0m"
     done
 }
 
@@ -56,11 +60,11 @@ function show_errors(){
 # Run test case
 #---------------------------------------------------------------------------------------
 function print_test_descr(){
-    descr="\n$1   : ${!1}"
-    echo -e "$descr"
+    descr="$1   : ${!1}"
+    echo_with_pid "$descr"
     if [ "$DBG" -eq 1 ]; then
         topts=$(quote_opts "${test_opts[@]}")
-        echo "cmd    : ../xml2xpath.sh $topts ${test_type_opts[*]}"
+        echo_with_pid "cmd    : ../xml2xpath.sh $topts ${test_type_opts[*]}"
     fi
 }
 
@@ -69,7 +73,7 @@ function print_test_descr(){
 #---------------------------------------------------------------------------------------
 function test_run(){
     if [ ! -f "${test_type_opts[${#test_type_opts[@]} - 1]}" ]; then
-        echo "ERROR file not found: ${test_type_opts[${#test_type_opts[@]} - 1]}"  | show_color
+        echo_with_pid "ERROR file not found: ${test_type_opts[${#test_type_opts[@]} - 1]}"  | show_color
         exit 1
     fi
     print_test_descr "$1"
@@ -82,4 +86,4 @@ function test_run(){
 #---------------------------------------------------------------------------------------
 function test_run_count(){
     ../xml2xpath.sh "${test_opts[@]}" "${test_type_opts[@]}" | wc -l
-}
\ No newline at end of file
+}
diff --git a/tests/test-xml-ns-01.sh b/tests/test-xml-ns-01.sh
index 74d944d..45f0fb9 100755
--- a/tests/test-xml-ns-01.sh
+++ b/tests/test-xml-ns-01.sh
@@ -13,7 +13,7 @@ test_opts=()
 test_type_opts=(-x "$xml_file")
 rel_xpath='/defaultns:ClinicalDocument/defaultns:recordTarget'
 
-echo "*** XML tests - namespaces on root element ($script_name) ***"
+echo_with_pid "*** XML tests - namespaces on root element ($script_name) ***"
 # Test case descriptions
 TC01="Basic test (-x)"
 TC02="Replace default namespace definition (-o), relative path (-s)"
diff --git a/tests/test-xml-ns-02.sh b/tests/test-xml-ns-02.sh
index 33d7eb8..1d08326 100755
--- a/tests/test-xml-ns-02.sh
+++ b/tests/test-xml-ns-02.sh
@@ -16,7 +16,7 @@ test_opts=()
 test_type_opts=(-x "$xml_file")
 rel_xpath='//incident'
 
-echo "*** XML tests - Namespaces on root element and body ($script_name) ***"
+echo_with_pid "*** XML tests - Namespaces on root element and body ($script_name) ***"
 # Test case descriptions
 TC01="Basic test (-x)"
 TC02="Replace default namespace definition (-o), relative path (-s)"
diff --git a/tests/test-xml-ns-03.sh b/tests/test-xml-ns-03.sh
index fec621f..f870141 100755
--- a/tests/test-xml-ns-03.sh
+++ b/tests/test-xml-ns-03.sh
@@ -19,7 +19,7 @@ xml_file="resources/html5.html"
 test_opts=()
 test_type_opts=(-x "$xml_file")
 
-echo "*** XHTML tests - Namespaces on root element and body. Multiple default namespaces across document. ($script_name) ***"
+echo_with_pid "*** XHTML tests - Namespaces on root element and body. Multiple default namespaces across document. ($script_name) ***"
 # Test case descriptions
 TC01="Basic test (-x)"
 TC02="Replace 'defaultns' prefix (-p)"
diff --git a/tests/test-xml-ns-no-default.sh b/tests/test-xml-ns-no-default.sh
index 9bb4b45..84e2985 100755
--- a/tests/test-xml-ns-no-default.sh
+++ b/tests/test-xml-ns-no-default.sh
@@ -9,7 +9,7 @@ xml_file="resources/nodefaultns.xml"
 test_opts=()
 test_type_opts=(-x "$xml_file")
 
-echo "*** XML tests - namespaces on root element but no default ns ($script_name) ***"
+echo_with_pid "*** XML tests - namespaces on root element but no default ns ($script_name) ***"
 # Test case descriptions
 TC01="Basic test (-x)"
 
diff --git a/xml2xpath.sh b/xml2xpath.sh
index db895cc..0339a6c 100755
--- a/xml2xpath.sh
+++ b/xml2xpath.sh
@@ -116,10 +116,10 @@ trap_with_arg() { # from https://stackoverflow.com/a/2183063/804678
 
 stop() {
   trap - SIGINT EXIT
-  printf '\n%s\n' "received $1, bye!"
+  printf '\n%s\n' "[$$] received $1, bye!"
   print_separator
   rm -f "$fifo_in" "$fifo_out";
-  pkill -f xmllint
+  pkill --parent $$ -f xmllint
   #kill -s SIGINT 0
 }
 
@@ -131,7 +131,7 @@ function print_separator(){
 # print to stderr
 #---------------------------------------------------------------------------------------
 function log_error(){
-    echo -e "$@" >> /dev/stderr
+    printf "%b" "$@" >> /dev/stderr
 }
 
 #---------------------------------------------------------------------------------------
@@ -167,9 +167,9 @@ function set_html_opts(){
 
 function is_read_error(){
     if [ "$1" -ge 128 ]; then
-        log_error "\nTimeout reading from file descriptor $1 $2 . Current timeout: $rtout secs. Try extending the timeout with: XML_XPATH_RTOUT=[int or float > $rtout] xml2xpath.sh ...\n"
+        log_error "\n[$$] Timeout reading from file descriptor $1 $2 . Current timeout: $rtout secs. Try extending the timeout with: XML_XPATH_RTOUT=[int or float > $rtout] xml2xpath.sh ...\n"
     elif [ "$1" -gt 0 ]; then
-        log_error "\nError reading from file descriptor: $1 $2\n"
+        log_error "\n[$$] Error reading from file descriptor: $1 $2\n"
     fi
     read_error="$1"
     return "$1"
@@ -427,12 +427,12 @@ function init_env(){
         ns_prefix="defaultns"
     fi
 
-    fifo_in='xffin'
-    fifo_out='xffout'
+    fifo_in="/tmp/xffin.$$"
+    fifo_out="/tmp/xffout.$$"
     trap_with_arg 'stop' EXIT SIGINT SIGTERM SIGHUP
     
-    [ ! -p "$fifo_in" ] && mkfifo "$fifo_in"
-    [ ! -p "$fifo_out" ] && mkfifo "$fifo_out"
+    [ ! -p "$fifo_in" ] && mkfifo --mode=600 "$fifo_in"
+    [ ! -p "$fifo_out" ] && mkfifo --mode=600 "$fifo_out"
     
     exec 3<>"$fifo_in"
     exec 4<>"$fifo_out"
@@ -504,7 +504,7 @@ fi
 # ################################################
 # Start process
 # ################################################
-echo -e "\nxml2xpath: find XPath expressions on $xml_file"
+echo -e "\n[$$] xml2xpath: find XPath expressions on $xml_file"
 print_separator
 echo
 printf "   %s\n" "${all_opts[@]}"