Python读取文件最后n行的方法

# -*- coding:utf8-*- import os import time import datetime import math import string def get_last_line(inputfile) : filesize = os.path.getsize(inputfile) blocksize = 1024 dat_file = open(inputfile, 'r') last_line = "" lines = dat_file.readlines() count = len(lines) if count>60: num=60 else: num=count i=1; lastre = [] for i in range(1,(num+1)): if lines : n = -i last_line = lines[n].strip() #print "last line : ", last_line dat_file.close() #print i lastre.append(last_line) return lastre #获取最后一行的结果 re = get_last_line('../update/log/rtime/rtime20130805.log') print len(re) for n in re: strlist = n.split(' ') if strlist[1] == 'ok' and string.atoi(strlist[2])>1000: print '数据条数正常' print 'OK' else: print '数据太少，检查发邮件'

2013-08-05 16:09:30 ok 1673 2013-08-05 16:10:34 ok 1628 2013-08-05 16:11:55 ok 71 2013-08-05 16:13:02 ok 1441 2013-08-05 16:14:06 ok 1634 2013-08-05 16:15:10 ok 1717 2013-08-05 16:16:14 ok 1687 2013-08-05 16:17:18 ok 1642 2013-08-05 16:18:27 ok 1655 2013-08-05 16:19:33 ok 1655

#返回文件最后一行函数 def get_last_line(inputfile) : filesize = os.path.getsize(inputfile) blocksize = 1024 dat_file = open(inputfile, 'r') last_line = "" if filesize > blocksize : maxseekpoint = (filesize // blocksize) dat_file.seek((maxseekpoint-1)*blocksize) elif filesize : #maxseekpoint = blocksize % filesize dat_file.seek(0, 0) lines = dat_file.readlines() if lines : last_line = lines[-1].strip() #print "last line : ", last_line dat_file.close() return last_line