ubuntu操作系统学习笔记之文本处理

红太狼 2023-10-16 19:52 18阅读 0赞

![Center][]

## 文件浏览 ##

cat : 显示全部内容  
more : 以向下翻页的方式查看内容  
less : 以向上/向下翻页的方式查看内容  
head : 查看头N行(默认10行)  
tail : 查看尾N行(默认10行)

## grep ##

说明 : 基于关键字搜索文本.  
Search for PATTERN in each FILE or standard input.  
格式 : grep \[OPTION\]... PATTERN \[FILE\]...  
可选项  
\-i : 忽略大小写

[root@wuqinfei wuqinfei]# grep 'WUQINFEI' /etc/passwd
    [root@wuqinfei wuqinfei]# grep -i 'WUQINFEI' /etc/passwd
    wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash

\-n : 显示结果所在行数

[root@wuqinfei wuqinfei]# grep -n 'wuqinfei' /etc/passwd
    35:wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash

\-v : 输出不带关键字的行  
\-A行数 : 输出匹配行之后的 N 行  
\-B行数 : 输出匹配行之前的 N 行

[root@wuqinfei wuqinfei]# grep -n 'wuqinfei' /etc/passwd
    35:wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash
    [root@wuqinfei wuqinfei]# grep -nB3 'wuqinfei' /etc/passwd
    32-abrt:x:173:173::/etc/abrt:/sbin/nologin
    33-sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
    34-tcpdump:x:72:72::/:/sbin/nologin
    35:wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash

示例  
$ grep 'wuqinfei' /etc/passwd  
\# find / -user wuqinfei | grep 'Video'

[wuqinfei@wuqinfei ~]$ grep 'wuqinfei' /etc/passwd
    wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash
    
    [root@wuqinfei wuqinfei]# find / -user wuqinfei | grep 'Video'
    find: `/proc/2317/task/2317/fd/5': No such file or directory
    find: `/proc/2317/task/2317/fdinfo/5': No such file or directory
    find: `/proc/2317/fd/5': No such file or directory
    find: `/proc/2317/fdinfo/5': No such file or directory
    /home/wuqinfei/Videos
    
    [root@wuqinfei wuqinfei]# find / -user wuqinfei 2> /etc/null | grep 'Video'
    /home/wuqinfei/Videos

## cut ##

说明 : 基于列 处理文本.  
Print selected parts of lines from each FILE to standard output.  
格式 : cut OPTION... \[FILE\]...  
选项  
\-d分隔符: delimiter, 指定分隔字符(默认是Tab)  
\-f列号 : fields, 输出切割后的第几列, 从1开始. -f1,2,3 -f1-3  
\-c : 基于字符进行切割; -c2-4 , 获得每行的第2到4个字符. (从1开始)  
示例  
\# cut -d: -f1 /etc/passwd  
\# grep wuqinfei /etc/passwd | cut -d: -f2  
\# grep wuqinfei /etc/passwd | cut -c1-4

[root@wuqinfei wuqinfei]# tail -n 3 /etc/passwd
    tcpdump:x:72:72::/:/sbin/nologin
    wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash
    user_a:x:501:501::/home/user_a:/bin/bash
    
    [root@wuqinfei wuqinfei]# tail -n 3 /etc/passwd | cut -d: -f1
    tcpdump
    wuqinfei
    user_a
    
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd
    wuqinfei:x:500:500:wuqinfei:/home/wuqinfei:/bin/bash
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd | cut -d: -f2
    x
    
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd | cut -d: -f1,2,3
    wuqinfei:x:500
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd | cut -d: -f1-3
    wuqinfei:x:500
    
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd | cut -d: -f1
    wuqinfei
    [root@wuqinfei wuqinfei]# grep wuqinfei /etc/passwd | cut -c1-4
    wuqi

## wc ##

说明 : 统计文本信息  
Print newline, word, and byte counts for each FILE, and a total line if  
more than one FILE is specified. With no FILE, or when FILE is -,  
read standard input.  
格式 : wc \[OPTION\]... \[FILE\]...  
选项  
\-l : 统计行数  
\-w : 单词数  
\-c : 字节数  
\-m : 字符数  
示例

[root@wuqinfei MyDir]# cat 1.txt
    hello
    hello world
    hello linux world
    [root@wuqinfei MyDir]# wc 1.txt
     3  6 36 1.txt
    [root@wuqinfei MyDir]# wc -l 1.txt
    3 1.txt
    [root@wuqinfei MyDir]# wc -w 1.txt
    6 1.txt
    [root@wuqinfei MyDir]# wc -c 1.txt
    36 1.txt
    [root@wuqinfei MyDir]# wc -m 1.txt
    36 1.txt

## sort ##

说明 : 对文本内容进行排序, 不会写入原文件.(基于ASCII码表)  
Write sorted concatenation of all FILE(s) to standard output.  
格式 : sort \[OPTION\]... \[FILE\]...  
选项  
\-r : 倒序  
\-n : 基于数字  
\-f : 忽略大小写  
\-u : 删除所有重复行 --unique. 也可使用 uniq命令删除相邻的重复行

[root@wuqinfei MyDir]# sort -u chs.txt
    aaa
    b
    
    [root@wuqinfei MyDir]# uniq chs.txt
    aaa
    b
    aaa

\-t分隔符: 先用字符"c"对每行分隔, 然后基于-k列号 排序

[root@wuqinfei MyDir]# cat chs.txt
    a:e:d
    c:b:a
    [root@wuqinfei MyDir]# sort chs.txt
    a:e:d
    c:b:a
    [root@wuqinfei MyDir]# sort -t: -k3 chs.txt
    c:b:a
    a:e:d

示例

[root@wuqinfei MyDir]# cat chs.txt
    b
    c
    a
    e
    d
    [root@wuqinfei MyDir]# sort chs.txt
    a
    b
    c
    d
    e
    [root@wuqinfei MyDir]# cat chs.txt
    b
    c
    a
    e
    d

## diff ##

说明 : 文本比较  
Compare files line by line.  
格式 : diff \[OPTION\]... FILES  
选项  
\-i : 忽略大小写  
\-b : 忽略空格  
\-u : 统一显示比较信息(一般用于生成patch文件)  
示例

[root@wuqinfei MyDir]# cat file
    aaaa
    bbbb
    [root@wuqinfei MyDir]# cp file file-new
    [root@wuqinfei MyDir]# ls -l
    total 8
    -rw-r--r--. 1 root root 10 Feb  3 13:45 file
    -rw-r--r--. 1 root root 10 Feb  3 13:46 file-new
    [root@wuqinfei MyDir]# echo "ccc" >> file-new
    [root@wuqinfei MyDir]# cat file-new
    aaaa
    bbbb
    ccc
    [root@wuqinfei MyDir]# diff file file-new
    2a3
    > ccc
    [root@wuqinfei MyDir]# diff -u file file-new
    --- file        2014-02-03 13:45:38.328922704 +0800
    +++ file-new    2014-02-03 13:46:38.050923691 +0800
    @@ -1,2 +1,3 @@
     aaaa
     bbbb
    +ccc
    [root@wuqinfei MyDir]# diff -u file file-new > file.patch

## tr ##

说明 : TRanslate, 处理文本内容.  
Translate, squeeze, and/or delete characters from standard input,  
writing to standard output.  
格式 : tr \[OPTION\]... SET1 \[SET2\]  
示例

[wuqinfei@wuqinfei MyDir]$ cat file
    hello, John.
    Mike, hello.
    
    [wuqinfei@wuqinfei MyDir]$ tr -d 'hello' < file
    , Jn.
    Mik, .
    
    [wuqinfei@wuqinfei MyDir]$ tr 'a-z' 'A-Z' < file
    HELLO, JOHN.
    MIKE, HELLO.

## sed ##

说明 : 搜索并替换文本内容  
格式 : sed \[OPTION\]... \{script-only-if-no-other-script\} \[input-file\]...  
示例: $ sed 's/a/b/g' file 将文件中所有a替换成b; s, search; g, global

[wuqinfei@wuqinfei MyDir]$ cat file
    aaaa
    aaaa
    [wuqinfei@wuqinfei MyDir]$ sed 's/a/b/' file
    baaa
    baaa
    [wuqinfei@wuqinfei MyDir]$ sed 's/a/b/g' file
    bbbb
    bbbb

示例: $ sed '2,4s/a/b/g' file 替换第2~4行

[wuqinfei@wuqinfei MyDir]$ cat file
    1aaaa
    2aaaa
    3aaaa
    4aaaa
    5aaaa
    [wuqinfei@wuqinfei MyDir]$ sed '2,4s/a/b/g' file
    1aaaa
    2bbbb
    3bbbb
    4bbbb
    5aaaa

示例: $ sed -f script-file file 调用文件中的script

[wuqinfei@wuqinfei MyDir]$ sed '2,4s/a/b/g' file
    1aaaa
    2bbbb
    3bbbb
    4bbbb
    5aaaa
    
    [wuqinfei@wuqinfei MyDir]$ echo '2,4s/a/b/g' > script-file
    [wuqinfei@wuqinfei MyDir]$ cat script-file
    2,4s/a/b/g
    
    [wuqinfei@wuqinfei MyDir]$ sed -f script-file  file
    1aaaa
    2bbbb
    3bbbb
    4bbbb
    5aaaa

示例: $ sed -e script1 -e script2 file 同时使用多个script

[wuqinfei@wuqinfei MyDir]$ sed '1,3s/a/b/g' file
    1bbbb
    2bbbb
    3bbbb
    4aaaa
    5aaaa
    [wuqinfei@wuqinfei MyDir]$ sed '4,5s/a/c/g' file
    1aaaa
    2aaaa
    3aaaa
    4cccc
    5cccc
    [wuqinfei@wuqinfei MyDir]$ sed -e '1,3s/a/b/g' -e '4,5s/a/c/g' file
    1bbbb
    2bbbb
    3bbbb
    4cccc
    5cccc

[Center]: https://img-blog.csdn.net/20140402140202375?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvemhvdXpoaXdlbmdhbmc=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/Center