diff --git a/prank.sh b/prank.sh
index 56dd8cdccf86cf693c2eea674393ab4841c24f6e..9a8a709fef9a97c683c819c9cb26b5436386ef55 100755
--- a/prank.sh
+++ b/prank.sh
@@ -11,7 +11,7 @@ EOF
 # rotating the screen during 10s evry 60s
 	cat << EOF
 function rotate_infinitly() {
-	SCREEN=$(xrandr -q | sed -n "s/^\(.*\) connected .*$/\1/p" | head -n 1)
+	SCREEN=\$(xrandr -q | sed -n "s/^\(.*\) connected .*$/\1/p" | head -n 1)
 	while true
 	do
 		sleep 60s
@@ -35,5 +35,5 @@ EOF
 	;;
 esac >> ~/.bashrc
 
-sleep 1s; sed -i '$ d' ~/.bash_history &
+(sleep 1s; sed -i '$ d' ~/.bash_history) &