MMAP'ed tail in python

tail.py

# Quick & Dirty... Full of bugs... Dont use for production code... You have been warned... ;-)
import mmap
import os

NUM_LINES=10

f=open('.bash_history', 'rb')

filesize = os.fstat(f.fileno()).st_size

mm =mmap.mmap(f.fileno(), 0, prot=mmap.PROT_READ)

pointer = filesize-1

if mm[pointer]=='\n':
  pointer=pointer-1

for i in range(NUM_LINES):
  while mm[pointer]!='\n':
    pointer=pointer-1
  pointer=pointer-1

pointer=pointer+1

print mm[pointer:]