sed 命令基础

# sed 笔记
一、替换[s]

1. -e选项 sed -e 's/dog/DOG/;s/cat/CAT/' test.txt
2. -f选项 sed -f sed.txt test.txt
3. -n选项 sed -n sed 's/dog/DOG/' test.txt
4. 数学方式行寻址 sed '2,3s/cat/CAT/' test.txt sed '3,$s/cat/CAT/' test.txt
5. 模式过滤器 sed '/is dog/s/dog/DOG/' test.txt
6. 命令组合 sed '2{s/dog/CAT/;s/pig/PIG/}' test.txt

二、全局匹配[g]

1. sed 's/dog/DOG/g' test.txt
2. sed 's/dog/DOG/3' test.txt

三、打印[p]

1. sed 's/dog/DOG/p' test.txt
2. sed -n '/line 4/{=;s/4/9p}' line.txt

四、写入文件[w]

1. sed 's/dog/DOG/w file.txt' test.txt

五、删除[d]

1. sed '2d' test.txt
2. sed '2, $d' test.txt
3. sed '/line 1/d' line.txt

六、插入[i,a]

1, sed '2i	his is insert line' line.txt
2. sed '$a	his is insert line' line.txt

七、修改[c]

1. sed '2c	his is update line' line.txt
2. sed '/line 4/c	his is update line' linet.txt

八、转换[y]

1. sed 'y/123/987/' line.txt

九、文件读[r]

1. sed '/line 3/r test.txt' line.txt
2. sed '/line 3/{r test.txt;d}' line.txt

# gawk 笔记
一、 打印[print]

1. gawk '{print "hello world"}'
2. gawk -F: '{print $1 "home is " $6}' /etc/passwd
3. gawk -F: -f test.awk /etc/passwd
4. gawk -F: '{$1=leng;print $0}' /etc/passwd

二、处理前后[BEGIN:END]

1. gawk 'BEGIN {print "this is file content"} {print $0} END{print "end file"}'