diff --git a/ecran b/ecran
index 3460706..ac51447 100755
--- a/ecran
+++ b/ecran
@@ -4,9 +4,6 @@
 #                   And reload wm configuration
 
 # Vars {{{
-## First and main screen (laptop screen,…)
-readonly MAIN_OUTPUT_NAME="LVDS-1"
-
 [ -z "${DEBUG}" ] && readonly DEBUG=0
 
 ## Colors
@@ -14,6 +11,10 @@ readonly PURPLE='\033[1;35m'
 readonly RED='\033[0;31m'
 readonly RESET='\033[0m'
 readonly COLOR_DEBUG="${PURPLE}"
+
+## First and main screen (laptop screen,…)
+readonly MAIN_OUTPUT_NAME="LVDS-1"
+
 # }}}
 
 debug_message() {                                               # {{{
@@ -38,15 +39,40 @@ The second connected output is: ${SECOND_OUTPUT_NAME}."
 	return "${return_second_output_name}"
 }
 # }}}
-main() {                                                        # {{{
+is_proc_running() {                                             # {{{
 
-	## Define all vars
-	define_vars
+	local_proc_pattern="${1}"
+
+	local_count_proc_pattern="$(pgrep -f -- "${local_proc_pattern}" | wc -l)"
+
+	case "${local_count_proc_pattern}" in
+		0 ) ## No procs related to this pattern are running
+			return_proc_running="1"
+			;;
+		* ) ## At least one proc seems running
+			return_proc_running="0"
+			;;
+esac
+
+	## Simple debug message to valid current variables
+	debug_message "is_proc_running − \
+procs running (with the pattern: ${RED}${local_proc_pattern}${COLOR_DEBUG}) on the current host: ${RED}${local_count_proc_pattern}${COLOR_DEBUG}."
+
+	return "${return_proc_running}"
 
 }
 # }}}
+main() {                                                        # {{{
 
-main
+	## Update herbstluftwm Window Manager configuration if it's running
+	is_proc_running "herbstluftwm" \
+		&& herbstclient detect_monitors \
+		&& herbstclient reload
+}
+# }}}
+
+## Define all vars
+define_vars
 
 # Manage arguments                                                # {{{
 # This code can't be in a function due to arguments
@@ -55,20 +81,20 @@ case "${1}" in
 		## TODO : One command to enable main screen and a loop to disable all other connected output
 		xrandr --output "${MAIN_OUTPUT_NAME:=/dev/null}" --auto --output "${SECOND_OUTPUT_NAME:=/dev/null}" --off --output VGA-1 --off --output HDMI-3 --off --output "${SECOND_OUTPUT_NAME:=/dev/null}" --off
 		xrandr --output VGA --off
-		printf 'Desactivate all video output'
+		printf "%b\n" 'Desactivate all video output'
 		;;
 	leftof | left-of | ds | dockstation | work )
 		#xrandr --output VGA-1 --mode 1024x768 --left-of "${MAIN_OUTPUT_NAME:=/dev/null}" --output "${MAIN_OUTPUT_NAME:=/dev/null}" --mode 1366x768
 		xrandr --output "${SECOND_OUTPUT_NAME:=/dev/null}" --auto --left-of "${MAIN_OUTPUT_NAME:=/dev/null}" --output "${MAIN_OUTPUT_NAME:=/dev/null}" --auto
-		printf 'Xrandr for second output left-of main screen'
+		printf "%b\n" 'Xrandr for second output left-of main screen'
 		;;
 	rightof | right-of | home )
 		xrandr --output "${SECOND_OUTPUT_NAME:=/dev/null}" --auto --right-of "${MAIN_OUTPUT_NAME:=/dev/null}" --output "${MAIN_OUTPUT_NAME:=/dev/null}" --auto
-		printf 'Xrandr for second output left-of main screen'
+		printf "%b\n" 'Xrandr for second output left-of main screen'
 		;;
 	above )
 		xrandr --output "${SECOND_OUTPUT_NAME:=/dev/null}" --auto --above "${MAIN_OUTPUT_NAME:=/dev/null}" --output "${MAIN_OUTPUT_NAME:=/dev/null}" --auto
-		printf 'Xrandr for dual screen with DisplayPort'
+		printf "%b\n" 'Xrandr for dual screen with DisplayPort'
 		;;
 	out | game )
 		xrandr --output "${SECOND_OUTPUT_NAME:=/dev/null}" --auto --output "${MAIN_OUTPUT_NAME:=/dev/null}" --off
@@ -77,15 +103,13 @@ case "${1}" in
 		xrandr --output "${MAIN_OUTPUT_NAME:=/dev/null}" --off
 		;;
 	* )
-		printf 'Bad argument, please use [vga|hdmi|ds|work|off]'
+		printf "%b\n" 'Bad argument, please use [vga|hdmi|ds|work|off]'
 		exit 1
 		;;
 esac
 
+main
+
 # }}}
 
-# Update herbstluftWM configuration
-herbstclient detect_monitors
-herbstclient reload
-
 exit 0