一天一个 Linux 命令（20）：sed 命令

sed [OPTION]... {script-only-if-no-other-script} [input-file]...

Usage: sed [OPTION]... {script-only-if-no-other-script} [input-file]...

  -n, --quiet, --silent
                 suppress automatic printing of pattern space
  -e script, --expression=script
                 add the script to the commands to be executed
  -f script-file, --file=script-file
                 add the contents of script-file to the commands to be executed
  --follow-symlinks
                 follow symlinks when processing in place
  -i[SUFFIX], --in-place[=SUFFIX]
                 edit files in place (makes backup if SUFFIX supplied)
  -c, --copy
                 use copy instead of rename when shuffling files in -i mode
  -b, --binary
                 does nothing; for compatibility with WIN32/CYGWIN/MSDOS/EMX (
                 open files in binary mode (CR+LFs are not treated specially))
  -l N, --line-length=N
                 specify the desired line-wrap length for the `l' command
  --posix
                 disable all GNU extensions.
  -r, --regexp-extended
                 use extended regular expressions in the script.
  -s, --separate
                 consider files as separate rather than as a single continuous
                 long stream.
  -u, --unbuffered
                 load minimal amounts of data from the input files and flush
                 the output buffers more often
  -z, --null-data
                 separate lines by NUL characters
  --help
                 display this help and exit
  --version
                 output version information and exit

If no -e, --expression, -f, or --file option is given, then the first
non-option argument is taken as the sed script to interpret.  All
remaining arguments are names of input files; if no input files are
specified, then the standard input is read.

参数说明：
-e<script>或--expression=<script> 指定sed动作，以选项中指定的script来处理输入的文本文件，可以由多个-e指定多个动作
-f<script文件>或--file=<script文件> 以选项中指定的script文件来处理输入的文本文件。直接将sed的动作写在一个文件内，-f filename则可以运行filename 内的sed动作；
-h或--help 显示帮助。
-n或--quiet或--silent 仅显示script处理后的结果。sed的一般用法中，所有来自STDIN的数据一般都会被打印到终端上，如果加上-n后，则只有经过sed特殊处理的那一行才会被列出来
-r或--regexp-extended：sed支持扩展正则表达式(默认是基础正则表达式)
-i ：直接修改读取的文件内容，而不是输出到终端。
-V或--version 显示版本信息。

动作说明：
a ：新增， a 的后面可以接字串，而这些字串会在新的一行出现(目前的下一行)～
c ：取代， c 的后面可以接字串，这些字串可以取代 n1,n2 之间的行！
d ：删除，因为是删除啊，所以 d 后面通常不接任何咚咚；
i ：插入， i 的后面可以接字串，而这些字串会在新的一行出现(目前的上一行)；
p ：打印，亦即将某个选择的数据印出。通常 p 会与参数 sed -n 一起运行～
s ：取代，可以直接进行取代的工作哩！通常这个s的动作可以搭配正规表示法！例如 1,10s/old/new/g 就是啦！

nl test.txt |sed '/joshua317/p'

#results:
# nl test.txt |sed '/joshua317/p'
     1  hello
     2  joshua317
     2  joshua317
     3  i
     4  love
     5  China
     6  ,
     7  joshua317
     7  joshua317
     8  my
     9  name
    10  yes

nl test.txt |sed -n '/joshua317/p'

#results:
# nl test.txt |sed -n '/joshua317/p'
     2  joshua317
     7  joshua317

nl test.txt | sed -n '3,6p'

#results:
# nl test.txt | sed -n '3,6p'
     3  i
     4  love
     5  China
     6  ,

nl test.txt | sed '/joshua317/d'

#results:
# nl test.txt | sed '/joshua317/d'
     1  hello
     3  i
     4  love
     5  China
     6  ,
     8  my
     9  name
    10  yes

# nl test.txt | sed  's/joshua317//g'
     1  hello
     2
     3  i
     4  love
     5  China
     6  ,
     7
     8  my
     9  name
    10  yes

# nl test.txt | sed  's/joshua317/joshua319/g'
     1  hello
     2  joshua319
     3  i
     4  love
     5  China
     6  ,
     7  joshua319
     8  my
     9  name
    10  yes

nl test.txt |sed "2a what's you name?"#results:#nl test.txt |sed "2a what's you name?"     1  hello     2  joshua317what's you name?     3  i     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt |sed "2i what's you name?"#results:# nl test.txt |sed "2i what's you name?"     1  hellowhat's you name?     2  joshua317     3  i     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt |sed "2i what's you name?\nnice to meet you"#results:# nl test.txt |sed "2i what's you name?\nnice to meet you"     1  hellowhat's you name?nice to meet you     2  joshua317     3  i     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

#results:# nl test.txt |sed "2i what's you name?\> \n\> nice to meet you \> "     1  hellowhat's you name?nice to meet you      2  joshua317     3  i     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt | sed '1,3d'#results:# nl test.txt | sed '1,3d'     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt | sed '2d'#results:# nl test.txt | sed '2d'     1  hello     3  i     4  love     5  China     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt | sed '3,$d'#results:# nl test.txt | sed '3,$d'     1  hello     2  joshua317

nl test.txt | sed '2,5c you are joshua317'#results:# nl test.txt | sed '2,5c you are joshua317'     1  helloyou are joshua317     6  ,     7  joshua317     8  my     9  name    10  yes

nl test.txt | sed  's/joshua317/joshua319/g'#results:# nl test.txt | sed 's/joshua317/joshua319/g'     1  hello     2  joshua319     3  i     4  love     5  China     6  ,     7  joshua319     8  my     9  name    10  yes

nl test.txt | sed -e '3,$d' -e 's/joshua317/joshua319/'#results:# nl test.txt | sed -e '3,$d' -e 's/joshua317/joshua319/'     1  hello     2  joshua319

sed -i 's/joshua317/joshua319/g' test.txt #results:# sed -i 's/joshua317/joshua319/g' test.txt [root@service-01 ~]# cat test.txt hellojoshua319iloveChina,joshua319mynameyes

sed -i '$a welcome to China' test.txt #results:# sed -i '$a welcome to China' test.txt [root@service-01 ~]# cat test.txt hellojoshua319iloveChina,joshua319mynameyeswelcome to China

sed -i '/joshua319/d' test.txt #results:# sed -i '/joshua319/d' test.txt [root@service-01 ~]# cat test.txt helloiloveChina,mynameyeswelcome to China