========不定期更新该页面========
1、只保留匹配的内容
日志片段：
"duration":0.03,"scheme":"https","sessionId":"19B0F3DD149FF8D81A4B4D68D53569F6","userId":"60800","path":"/mobile/index.html"
sed -n 's/^.*\("userId":"[0-9]*"\).*$/\1/p' logfile.txt首先想到搞个python，后来又觉得麻烦了点，果断google得来上面的命令
python可以这样：
import re
f = open("logfile.txt")
p = re.compile(r'"userId":"\d+"')
for line in f:
m = p.search(line)
print m.group(0)2、查看指定行范围的内容
sed -n '2,5p' backtask.py
3、在匹配行的下面插入
sed '0,/Matched Keyword/s//Matched Keyword\nNew Inserted Line/' myfile.txt sed -i '/tracker_server=10.45.11.37:22122/a tracker_server=10.45.11.37:22123' /etc/fdfs/storage.conf
