Shell Script to detect events in ADB Logcat in a loop

The following shell script performs an action (tap) on the screen, then checks that a particular event does not happen on the device. It then performs another action (press back button) and then checks the target event happens only once. Then it closes a process and iterates through the same steps in a loop 50 times.

#!/bin/sh

# Clean up any reminiscent from previous run of the script
rm -rf script_logs
mkdir script_logs
for i in {1..50}
do
	echo $i
	echo "Clearing device logs"
	adb logcat -c
	echo "Starting log recording"
	adb logcat >> script_logs/script_logs$i.txt &
	logcat_pid=$!
	echo "Clicking at a point on the screen"
	adb shell input tap 200 300
	echo "Waiting for 4 seconds for event to happen and logs generated"
	sleep 4
	events=`grep "<log_pattern>" script_logs/script_logs$i.txt | wc -l`
	if [ $events == 0 ]
	then
		echo "No event found"
	else
		echo "$events were found, the test failed"
		kill -9 $logcat_pid
		exit 1
	fi
	adb shell input keyevent KEYCODE_BACK
	echo "Waiting for 4 seconds for another event"
	sleep 4
	echo "Checking how many events were sent"
	events=`grep "<log_pattern>" script_logs/script_logs$i.txt | wc -l`
	if [ $events == 1 ]
	then
		echo "One and only one event was found"
	else
		echo "$events were found, the test failed"
		kill -9 $logcat_pid
		exit 1
	fi
	echo "Killing target process"
	pid=`adb shell pidof <process_name>`
	adb shell kill -9 $pid
	echo "Stopping logcat"
	kill -9 $logcat_pid
	sleep 2
done