Linux之常用命令awk,sed ，grep以及如何查看日志来定位具体问题
文本处理命令
Awk：功能比较强大，可以有比较强大的计算逻辑在里面，sed主要用来对文本进行替换和删除，逐行扫描。grep只是单纯查找
简介
https://en.wikipedia.org/wiki/AWK
https://www6.software.ibm.com/developerworks/education/au-gawk/au-gawk-a4.pdf
linux 和 mac 的兼容性
https://stackoverflow.com/questions/24332942/why-awk-script-does-not-work-on-mac-os-but-works-on-linux
cat my_shoping.list
No Item_Name Unit_Price Quantity Price
1 Mouse #20,000 1 #20,000
2 Monitor #500,000 1 #500,000
3 RAM_Chips #150,000 2 #300,000
4 Ethernet_Cables #30,000 4 #120,000
from file or as filter
pattern
awk '{print}' my_shoping.list
awk '//' my_shoping.list
awk '/Mouse/ || /Mon/ {print }' my_shoping.list
awk '/Mouse/ && /Mon/ {print }' my_shoping.list
awk '/M/ && /20,000/ {print }' my_shoping.list
awk '/green/ { print }' sample
awk '/!.*!/' sample
awk '$3 ~ /is/ ' sample
awk 'BEGIN {FS=":"} $7 !~ /false/ {print $5}' /etc/passwd
cat my_shoping.list| awk '//'
awk '{ print $1 } ' sample
awk ' BEGIN { FS = "!" } { print $1 } ' sample
awk ' BEGIN { FS = "," } { print $1 } ' sample
key words
$0, $1, NR, NF
sed
https://likegeeks.com/sed-linux/
替换
sed 's/unix/linux/' geekfile.txt
sed 's/unix/linux/2' geekfile.txt
sed 's/unix/linux/g' geekfile.txt
sed '3 s/unix/linux/' geekfile.txt
cat geekfile.txt
sed 's/unix/linux/p' geekfile.txt
sed -n 's/unix/linux/p' geekfile.txt
sed '1,3 s/unix/linux/' geekfile.txt
删除
sed '2d' geekfile.txt
sed '$d' geekfile.txt
sed '1,2d' geekfile.txt
sed '2,$d' geekfile.txt
sed '/learn/' geekfile.txt
sed '/learn/d' geekfile.txt
修改原文件
sed -i bak 's/unix/linux/g' geekfile.txt
grep
https://www.linuxtechi.com/linux-grep-command-with-14-different-examples/
grep daniel /etc/passwd
grep root /etc/passwd
grep root /etc/passwd /etc/gshadow
grep -l Price ./*
grep Price ./*
grep -n Price ./*
grep -vn Price ./*
grep ^No food_list.txt
grep No food_list.txt
grep '^No' food_list.txt
grep ^No food_list.txt
grep '^1' food_list.txt
grep 'Price$' food_list.txt
grep -r root /etc
grep -rl root /etc
grep -i price ./*
man grep
grep -e "linux" geekfile.txt
grep -e "linux" -e
grep -e "great" -e
grep -f grep_pattern /etc/passwd
grep -f grep_pattern1 geekfile.txt
grep -f grep_pattern1 geekfile.txt
grep -f grep_pattern1 geekfile.txt
head， tail
head -n 2 food_list.txt
tail -n 2 food_list.txt
tail -c 20 food_list.txt
head -c 20 food_list.txt
tail -fn 200 food_list.txt
cat , less，more
man
cat 连接多个文件，一次显示
cat food_list.txt my_shoping.list
less is more
快捷键提示 h
## sort， uniq
cat sort.txt
sort sort.txt
sort -u sort.txt
uniq sort.txt
uniq sort.txt
sort -u sort.txt
vim sort-nrkt.txt
cat sort-nrkt.txt
sort -nk 2 -t: sort-nrkt.txt
sort -nkr 3 -t: sort-nrkt.txt
sort -nrk 3 -t: sort-nrkt.txt
uniq -d sort.txt
uniq -cd sort.txt
uniq -c sort.txt
uniq -d sort.txt
统计响应时间超过5秒的接口： cat www-ccbscf-access1.log | awk 'BEGIN { FS = "[|]+"}; /\|\|/&& /09\/Apr/ && $NF >5 {print $2, $3, $NF} '|sort -t ' ' -rnk 6
日志查看
## 确定哪个日志
ls -lrt
## 先到api-web
http://test2.ccbscf.com/api/web/biz/v1/corps/invoices/list?name=&invoiceType=&mailBusinessType=INVOICE&page=1&pageSize=10
http://12.0.216.145:19001/eureka/apps
less ccbscf-api-web.log
可以先到 日志文件的最后，倒序查找
## 如何区分出特定请求的日志
tail -fn 200 ccbscf-api-web.log |grep -C 10 'biz/v1/corps/invoices/list'
grep -C 5 'biz/v1/corps/invoices/list' ccbscf-api-web.log|tail -10
# 后台执行
nohup/setsid/&
ping www.taobao.com
nohup ping www.taobao.com
nohup ping www.taobao.com &
(ping www.ibm.com &)
screen -S ping-test
screen -l
screen ls
screen ls
screen -ls
screen -rAd ping-test
screen -rAd ping-test