一、替换(s)
详细用法 [address]s/pattern/replacement/flags
修饰flag的标志如下:
命令 | 说明 |
n | 1到512之间的一个数字,表示文本模式中指定模式第n次出现的情况进行替换 |
g | 对模式空间的所有出现的情况进行全局更改,没有g通常只有第一次出现的情况被取代 |
p | 打印模式空间的内容 |
w file | 将模式空间的内容写到文件file中 |
x | 表示互换模板块中的文本和缓冲区中的文本 |
y | 表示把一个字符翻译为另外的字符(但是不用于正则表达式) |
& | 已匹配字符串标记 |
准备测试文件:
[kumufengchun@localhost ~]$ cat replace.txt my name is Lily This is your dog my dog's name is frank This is your fish my fish's name is george This is your goat my goat's name is adam
替换文本中的字符串
[kumufengchun@localhost ~]$ sed 's/This/That/' replace.txt my name is Lily That is your dog my dog's name is frank That is your fish my fish's name is george That is your goat my goat's name is adam
上述命令只是替换每行的第一个,如果替换所有的需要 用 sed 's/This/That/g' replace.txt
打印替换行
[kumufengchun@localhost ~]$ sed 's/This/That/p' replace.txt my name is Lily That is your dog That is your dog my dog's name is frank That is your fish That is your fish my fish's name is george That is your goat That is your goat my goat's name is adam
-n选项和p命令一起使用表示只打印那些发生替换的行
[kumufengchun@localhost ~]$ sed -n 's/This/That/p' replace.txt That is your dog That is your fish That is your goat
直接编辑文件选项-i,会匹配文件中每一行的第一个This替换为That,即在原文件中修改
[kumufengchun@localhost ~]$ sed -i 's/This/That/' replace.txt [kumufengchun@localhost ~]$ cat replace.txt my name is Lily That is your dog my dog's name is frank That is your fish my fish's name is george That is your goat my goat's name is adam
当需要从第N处匹配开始替换时,可以使用/Ng:
修改下文件如下:
[kumufengchun@localhost ~]$ cat replace.txt my name is Lily that is your that dog my dog's name is frank that is your that fish my fish's name is george that is your that goat my goat's name is adam [kumufengchun@localhost ~]$ sed 's/that/this/2g' replace.txt my name is Lily that is your this dog my dog's name is frank that is your this fish my fish's name is george that is your this goat my goat's name is adam
定界符出现在样式内部时,需要进行转义
[kumufengchun@localhost ~]$ echo '/usr/local/bin' | sed 's//usr/local/bin//USR/LOCAL/BIN/g' /USR/LOCAL/BIN
命令中的三根斜线分隔符可以换成别的符号,有时候替换目录字符串的时候有较多斜线,这个时候换成其它的分割符是较为方便,只需要紧跟s定义即可
[kumufengchun@localhost ~]$ sed 's?that?this?2g' replace.txt my name is Lily that is your this dog my dog's name is frank that is your this fish my fish's name is george that is your this goat my goat's name is adam [kumufengchun@localhost ~]$ sed 's|that|this|2g' replace.txt my name is Lily that is your this dog my dog's name is frank that is your this fish my fish's name is george that is your this goat my goat's name is adam
”^”表示行首
”$”符号如果在引号中表示行尾,但是在引号外却表示末行(最后一行)
# 注意这里的 " & " 符号,如果没有 “&”,就会直接将匹配到的字符串替换掉
sed 's/^/添加的头部&/g' #在所有行首添加
sed 's/$/&添加的尾部/g' #在所有行末添加
sed '2s/原字符串/替换字符串/g' #替换第2行
sed '$s/原字符串/替换字符串/g' #替换最后一行
sed '2,5s/原字符串/替换字符串/g' #替换2到5行
sed '2,$s/原字符串/替换字符串/g' #替换2到最后一行
[kumufengchun@localhost ~]$ sed 's/^/添加的头部&/g' replace.txt 添加的头部my name is Lily 添加的头部that is your that dog 添加的头部my dog's name is frank 添加的头部that is your that fish 添加的头部my fish's name is george 添加的头部that is your that goat 添加的头部my goat's name is adam [kumufengchun@localhost ~]$ sed 's/$/&添加的尾部/g' replace.txt my name is Lily添加的尾部 that is your that dog添加的尾部 my dog's name is frank添加的尾部 that is your that fish添加的尾部 my fish's name is george添加的尾部 that is your that goat添加的尾部 my goat's name is adam添加的尾部 [kumufengchun@localhost ~]$ sed '2s/that/jiao/g' replace.txt my name is Lily jiao is your jiao dog my dog's name is frank that is your that fish my fish's name is george that is your that goat my goat's name is adam [kumufengchun@localhost ~]$ sed '$s/my/your/g' replace.txt my name is Lily that is your that dog my dog's name is frank that is your that fish my fish's name is george that is your that goat your goat's name is adam [kumufengchun@localhost ~]$ sed '2,5s/my/your/g' replace.txt my name is Lily that is your that dog your dog's name is frank that is your that fish your fish's name is george that is your that goat my goat's name is adam [kumufengchun@localhost ~]$ sed '2,$s/my/your/g' replace.txt my name is Lily that is your that dog your dog's name is frank that is your that fish your fish's name is george that is your that goat your goat's name is adam
同时执行两个替换规则,sed 's/^/添加的头部&/g;s/$/&添加的尾部/g'
[kumufengchun@localhost ~]$ sed 's/^/添加的头部&/g;s/$/&添加的尾部/g' replace.txt 添加的头部my name is Lily添加的尾部 添加的头部that is your that dog添加的尾部 添加的头部my dog's name is frank添加的尾部 添加的头部that is your that fish添加的尾部 添加的头部my fish's name is george添加的尾部 添加的头部that is your that goat添加的尾部 添加的头部my goat's name is adam添加的尾部
二、删除(d)
删除空白行
[kumufengchun@localhost ~]$ cat sed.txt my cat's name is betty This is your This dog my dog's name is This frank This is your fish my fish's name is This george This is your goat my goat's name is This adam [kumufengchun@localhost ~]$ sed '/^$/d' sed.txt my cat's name is betty This is your This dog my dog's name is This frank This is your fish my fish's name is This george This is your goat my goat's name is This adam
删除第2行
[kumufengchun@localhost ~]$ sed '2d' sed.txt my cat's name is betty This is your This dog my dog's name is This frank This is your fish my fish's name is This george This is your goat my goat's name is This adam
删除文件的第2行到末尾所有行
[kumufengchun@localhost ~]$ sed '2,$d' sed.txt my cat's name is betty
删除文件最后一行
[kumufengchun@localhost ~]$ sed '$d' sed.txt my cat's name is betty This is your This dog my dog's name is This frank This is your fish my fish's name is This george This is your goat
删除文件中所有以my开头的行
[kumufengchun@localhost ~]$ sed '/^my/d' sed.txt This is your This dog This is your fish This is your goat
-e选项允许在同一行里执行多条命令
[kumufengchun@localhost ~]$ sed -e '1,5d' -e 's/my/MY/' sed.txt This is your fish MY fish's name is This george This is your goat MY goat's name is This adam
删除不连续的行 ##注意这里不能添加引号或者双引号,否则报错
[kumufengchun@localhost ~]$ sed -e{2,4}d sed.txt my cat's name is betty This is your This dog This is your fish my fish's name is This george This is your goat my goat's name is This adam
三、列表(l)
列表命令(l)可用于显示模式空间的内容,将非打印的字符显示为两个数字的ASCII码。可以使用该命令来检测输入中的不可见字符
[kumufengchun@localhost ~]$vim list.txt 19楼浙江家博会^I^A19lou.com^A^A^A$ 19楼 装修^I^A19lou.com^A^A^A$ 杭州19楼家博会^I^A19lou.com^A^A^A$ 杭州19楼家博会下一季时间^I^A19lou.com^A^A^A$ 杭州19楼装修^I^A19lou.com^A^A^A$ 杭州19楼装饰^I^A19lou.com^A^A^A$ 杭州装修19楼^I^A19lou.com^A^A^A$
[kumufengchun@localhost ~]$sed "l" list.txt
19楼浙江家博会 19lou.com
19346245274 350243205344277256 00119lou.com