python实现定时提取实时日志程序

#!/usr/local/bin/python 
# coding:utf-8 
 
import fileinput 
import time 
import os 
 
target_file = 'user.log' 
init_flag = True # 初次加载程序 
time_kick = 5 
 
record_count = 0 
 
while True: 
 print '当前读到了', record_count 
 #没有日志文件，等待 
 if not os.path.exists(target_file): 
 print 'target_file not exist' 
 time.sleep(time_kick) 
 continue 
 
 try: 
 ip = '10.10.1.100' 
 easytime = time.strftime('%Y%m%d_%H%M%S', time.localtime()) 
 file_name = '%s_user_%s.log' % (ip,easytime) 
 f_w = open(file_name, 'w') 
 if init_flag: 
  #读取整个文件 
  for eachline in fileinput.input(target_file): 
  print eachline 
  f_w.write(eachline) 
  record_count += 1 
 
  init_flag = False 
 else: 
  #如果总行数小于当前行，那么认为文件更新了，从第一行开始读。 
  total_count = os.popen('wc -l %s' % target_file).read().split()[0] 
  total_count = int(total_count) 
  if total_count < record_count: 
  record_count = 0 
 
  for eachline in fileinput.input(target_file): 
  line_no = fileinput.filelineno() 
  if line_no > record_count: 
   print eachline 
   f_w.write(eachline) 
   record_count += 1 
 
 f_w.close() 
 except: 
 pass 
 time.sleep(time_kick)