Put file inside while True like so
while True:
f = open('torecv.png','wb')
c, addr = s.accept() # Establish connection with client.
print 'Got connection from', addr
print "Receiving..."
l = c.recv(1024)
while (l):
print "Receiving..."
f.write(l)
l = c.recv(1024)
f.close()
print "Done Receiving"
c.send('Thank you for connecting')
c.close()