readerWRIter.py

from multiprocessing import Process,Queue
import time
from threading import Thread


def writer(wrt,arr):
	x=0
	while wrt==0:
		x+=1
	wrt=0
	arr.append(1)
	wrt=1

def reader(wrt,mutex,arr,readcount):
	x=0
	while mutex==0:
		x+=1
	readcount+=1
	if readcount==1:
		while wrt==0:
			x+=1
	mutex=1


	for i in arr:
		print("arr elements are",i)

	while mutex==0:
		x+=1
	readcount-=1
	if readcount==0:
		wrt=1
	mutex=1

arr=[]
mutex=1
wrt=1
readcount=0
t1=Thread(target=writer,args=(wrt,arr,))
t2=Thread(target=reader,args=(wrt,mutex,arr,readcount,))
t3=Thread(target=writer,args=(wrt,arr,))
t4=Thread(target=reader,args=(wrt,mutex,arr,readcount,))
t1.start()
time.sleep(3)
t2.start()
time.sleep(3)
t3.start()
time.sleep(3)
t4.start()