使用正则表达式从python中的readline()获取一些子字符串

对于第一部分,获取时间戳、ID和偏移量。

我相信这是一个粗俗的瑞格舞娘。

>>> import re
>>> l = '23:30:43.170344 IP (tos 0x0, ttl 64, id 55731, offset 0, flags [DF], proto TCP (6), length 443)'
>>> k = re.compile(r'^([0-9:]+\.[0-9]+) IP \(.* id ([0-9]+), offset ([0-9]+).*\)')
>>> x = k.match(l)
>>> x.groups()
('23:30:43.170344', '55731', '0')
>>> x.groups()[0]
'23:30:43.170344'
>>> x.groups()[1]
'55731'
>>> x.groups()[2]
'0'
>>> 

第二部分:

>>> l = '192.168.98.138.49341 > 201.20.49.239.80: Flags [P.], seq 562034569:562034972, ack 364925832, win 5840, length 403'
>>> k = re.compile(r'^([0-9.]+) > ([0-9.]+): .* seq ([0-9:]+), ack ([0-9]+).*')
>>> x = k.match(l)
>>> for y in x.groups(): print y
... 
192.168.98.138.49341
201.20.49.239.80
562034569:562034972
364925832

有关RE模块的阅读:

• http://www.doughellmann.com/PyMOTW/re/