如何改善这种尾巴状的Python鳕鱼

Question

我只想知道你们有没有比我想出的更好的方法。我想要的是制作一个类似“tail-f”的脚本，但它会主动查找字符串，并实时打印与该字符串相关的文本。正如你从代码中看到的，我在寻找MAC地址，但我想它可能会被用于其他目的。在

我在想一定有更好的方法来做这件事。也许你们中有人知道一个聪明的算法或者一个更好的命令。谢谢你的帮助

import time, os, sys
from datetime import date

# Function to get the file size, it will help us go to the end of a file
def current_file_size(filename):
    file_results = os.stat(filename)
    file_size = file_results[6]
    return file_size

# Check for correct usage
if len(sys.argv) != 2:
    print "Usage: %s <mac_address>" % sys.argv[0]
    sys.exit()

#Get the date in the format that the log uses
now = date.today()
todays_date = now.strftime("%Y%m%d")

#Set the filename and open the file
filename = 'complete.log'
file = open(filename,'r')

#Find the size of the file and move to the end
st_size = current_file_size(filename)
file.seek(st_size)

while 1:
    where = file.tell()   # current position of the file
    time.sleep(2)         # sleep for a little while
    st_size = current_file_size(filename)
    if st_size > where:       # if there's new text
        alotoflines = file.read(st_size-where)    # get the new lines as a group
        # search for the tag+mac address
        found_string = alotoflines.find("<mac v=\"" + sys.argv[1])
        if found_string > 0:
            # search for the immediately prior date instance from where the MAC address
            # is. I know that the log entry starts there
            found_date_tag = alotoflines.rfind(todays_date,0,found_string)
            print alotoflines[found_date_tag:]

Answer 1

您是在做Python练习还是可以使用shell？在

您可以简单地将尾部输出导入grep吗？在

tail -F myfile.txt | egrep  line-buffered myPattern

您可以将它放入一个脚本中，并生成文件和模式参数。在

使用grep还可以通过使用-A和-B开关向输出添加上下文。在