Linux系统操作

Linux系统发行版本

  1. Redhat
  2. Ubuntu
  3. CentOS
  4. Fedora
  5. Debian
  6. openSUSE

基础命令

Linux系统的命令通常都是如下所示的格式:

命令名称 [命名参数] [命令对象]
  1. 获取登录信息 - w / who / last

    [root@izwz97tbgo9lkabnat2lo8z ~]# w
     23:31:16 up 12:16,  2 users,  load average: 0.00, 0.01, 0.05
    USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
    root     pts/0    182.139.66.250   23:03    4.00s  0.02s  0.00s w
    jackfrue pts/1    182.139.66.250   23:26    3:56   0.00s  0.00s -bash
    [root@izwz97tbgo9lkabnat2lo8z ~]# who
    root     pts/0        2018-04-12 23:03 (182.139.66.250)
    jackfrued pts/1        2018-04-12 23:26 (182.139.66.250)
    [root@izwz97tbgo9lkabnat2lo8z ~]# who am i
    root     pts/0        2018-04-12 23:03 (182.139.66.250)
    
  2. 查看自己使用的Shell - ps

    Shell也被称为“壳”,它是用户与内核交流的翻译官,简单的说就是人与计算机交互的接口。目前很多Linux系统默认的Shell都是bash(Bourne Again SHell),因为它可以使用Tab键进行命令补全、可以保存历史命令、可以方便的配置环境变量以及执行批处理操作等。

    [root@izwz97tbgo9lkabnat2lo8z ~]# ps
      PID TTY          TIME CMD
     3531 pts/0    00:00:00 bash
     3553 pts/0    00:00:00 ps
    
  3. 查看命令的说明 - whatis

    [root@izwz97tbgo9lkabnat2lo8z ~]# whatis ps
    ps (1)        - report a snapshot of the current processes.
    [root@izwz97tbgo9lkabnat2lo8z ~]# whatis python
    python (1)    - an interpreted, interactive, object-oriented programming language
    
  4. 查看命令的位置 - which / whereis

    [root@izwz97tbgo9lkabnat2lo8z ~]# whereis ps
    ps: /usr/bin/ps /usr/share/man/man1/ps.1.gz
    [root@izwz97tbgo9lkabnat2lo8z ~]# whereis python
    python: /usr/bin/python /usr/bin/python2.7 /usr/lib/python2.7 /usr/lib64/python2.7 /etc/python /usr/include/python2.7 /usr/share/man/man1/python.1.gz
    [root@izwz97tbgo9lkabnat2lo8z ~]# which ps
    /usr/bin/ps
    [root@izwz97tbgo9lkabnat2lo8z ~]# which python
    /usr/bin/python
    
  5. 查看帮助文档 - man / info / apropos

    [root@izwz97tbgo9lkabnat2lo8z ~]# ps --help
    Usage:
     ps [options]
     Try 'ps --help '
      or 'ps --help '
     for additional help text.
    For more details see ps(1).
    [root@izwz97tbgo9lkabnat2lo8z ~]# man ps
    PS(1)                                User Commands                                PS(1)
    NAME
           ps - report a snapshot of the current processes.
    SYNOPSIS
           ps [options]
    DESCRIPTION
    ...
    [root@izwz97tbgo9lkabnat2lo8z ~]# info ps
    ...
    
  6. 切换用户 - su

    [root@izwz97tbgo9lkabnat2lo8z ~]# su hellokitty
    [hellokitty@izwz97tbgo9lkabnat2lo8z root]$
    
  7. 以管理员身份执行命令 - sudo

    [jackfrued@izwz97tbgo9lkabnat2lo8z ~]$ ls /root
    ls: cannot open directory /root: Permission denied
    [jackfrued@izwz97tbgo9lkabnat2lo8z ~]$ sudo ls /root
    [sudo] password for jackfrued:
    calendar.py  code  error.txt  hehe  hello.c  index.html  myconf  result.txt
    

    说明:如果希望用户能够以管理员身份执行命令,用户必须被添加到sudoers名单中,该文件在 /etc目录下。

  8. 登入登出相关 - logout / exit / adduser / userdel / passwd / ssh

    [root@izwz97tbgo9lkabnat2lo8z ~]# adduser hellokitty
    [root@izwz97tbgo9lkabnat2lo8z ~]# passwd hellokitty
    Changing password for user jackfrued.
    New password:
    Retype new password:
    passwd: all authentication tokens updated successfully.
    [root@izwz97tbgo9lkabnat2lo8z ~]# ssh [email protected]
    [email protected]'s password:
    Last login: Thu Apr 12 23:05:32 2018 from 10.12.14.16
    [hellokitty@izwz97tbgo9lkabnat2lo8z ~]$ logout
    Connection to 1.2.3.4 closed.
    [root@izwz97tbgo9lkabnat2lo8z ~]#
    
  9. 查看系统和主机名 - uname / hostname

    [root@izwz97tbgo9lkabnat2lo8z ~]# uname
    Linux
    [root@izwz97tbgo9lkabnat2lo8z ~]# hostname
    izwz97tbgo9lkabnat2lo8z
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat /etc/centos-release
    CentOS Linux release 7.4.1708 (Core) 
    
  10. 重启和关机 - reboot / init 6 / shutdown / init 0

  11. 查看历史命令 - history

```source-shell
[root@iZwz97tbgo9lkabnat2lo8Z ~]# history
...
452  ls
453  cd Python-3.6.5/
454  clear
455  history
[root@iZwz97tbgo9lkabnat2lo8Z ~]# !454
```

> 说明:查看到历史命令之后,可以用`!历史命令编号`来重新执行该命令;通过`history -c`可以清除历史命令。

实用程序

文件和文件夹操作

  1. 创建/删除目录 - mkdir / rmdir

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# mkdir abc
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# mkdir -p xyz/abc
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# rmdir abc
    
  2. 创建/删除文件 - touch / rm

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# touch readme.txt
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# touch error.txt
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# rm error.txt
    rm: remove regular empty file ‘error.txt’? y
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# rm -rf xyz
    
    • touch命令用于创建空白文件或修改文件时间。在Linux系统中一个文件有三种时间:
      • 更改内容的时间 - mtime。
      • 更改权限的时间 - ctime。
      • 最后访问时间 - atime。
    • rm的几个重要参数:
      • -i:交互式删除,每个删除项都会进行询问。
      • -r:删除目录并递归的删除目录中的文件和目录。
      • -f:强制删除,忽略不存在的文件,没有任何提示。
  3. 切换和查看当前工作目录 - cd / pwd

    说明:cd命令后面可以跟相对路径(以当前路径作为参照)或绝对路径(以/开头)来切换到指定的目录,也可以用cd ..来返回上一级目录。

  4. 查看目录内容 - ls

    • -l:以长格式查看文件和目录。
    • -a:显示以点开头的文件和目录(隐藏文件)。
    • -R:遇到目录要进行递归展开(继续列出目录下面的文件和目录)。
    • -d:只列出目录,不列出其他内容。
    • -S/-t:按大小/时间排序。
  5. 查看文件内容 - cat / head / tail / more / less

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# wget http://www.sohu.com/ -O sohu.html
    --2018-06-20 18:42:34--  http://www.sohu.com/
    Resolving www.sohu.com (www.sohu.com)... 14.18.240.6
    Connecting to www.sohu.com (www.sohu.com)|14.18.240.6|:80... connected.
    HTTP request sent, awaiting response... 200 OK
    Length: 212527 (208K) [text/html]
    Saving to: ‘sohu.html’
    100%[==================================================>] 212,527     --.-K/s   in 0.03s
    2018-06-20 18:42:34 (7.48 MB/s) - ‘sohu.html’ saved [212527/212527]
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat sohu.html
    ...
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# head -10 sohu.html
    
    
    
    搜狐
    
    
    
    
    
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# tail -2 sohu.html
    
    
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# less sohu.html
    ...
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat -n sohu.html | more
    ...
    
  6. 拷贝/移动文件 - cp / mv

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# mkdir backup
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cp sohu.html backup/
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cd backup
    [root@iZwz97tbgo9lkabnat2lo8Z backup]# ls
    sohu.html
    [root@iZwz97tbgo9lkabnat2lo8Z backup]# mv sohu.html sohu_index.html
    [root@iZwz97tbgo9lkabnat2lo8Z backup]# ls
    sohu_index.html
    
  7. 查找文件和查找内容 - find / grep

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# find / -name "*.html"
    /root/sohu.html
    /root/backup/sohu_index.html
    [root@izwz97tbgo9lkabnat2lo8z ~]# find . -atime 7 -type f -print
    [root@izwz97tbgo9lkabnat2lo8z ~]# find . -type f -size +2k
    [root@izwz97tbgo9lkabnat2lo8z ~]# find . -type f -name "*.swp" -delete
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# grep "
    24:
    25:
    26:
    29:
    ...
    

    说明:grep在搜索字符串时可以使用正则表达式,如果需要使用正则表达式可以用grep -E或者直接使用egrep

  8. 链接 - ln

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls -l sohu.html
    -rw-r--r-- 1 root root 212131 Jun 20 19:15 sohu.html
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ln /root/sohu.html /root/backup/sohu_backup
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls -l sohu.html
    -rw-r--r-- 2 root root 212131 Jun 20 19:15 sohu.html
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ln /root/sohu.html /root/backup/sohu_backup2
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls -l sohu.html
    -rw-r--r-- 3 root root 212131 Jun 20 19:15 sohu.html
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ln -s /etc/centos-release sysinfo
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls -l sysinfo
    lrwxrwxrwx 1 root root 19 Jun 20 19:21 sysinfo -> /etc/centos-release
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat sysinfo
    CentOS Linux release 7.4.1708 (Core)
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat /etc/centos-release
    CentOS Linux release 7.4.1708 (Core)
    

    说明:链接可以分为硬链接和软链接(符号链接)。硬链接可以认为是一个指向文件数据的指针,就像Python中对象的引用计数,每添加一个硬链接,文件的对应链接数就增加1,只有当文件的链接数为0时,文件所对应的存储空间才有可能被其他文件覆盖。我们平常删除文件时其实并没有删除硬盘上的数据,我们删除的只是一个指针,或者说是数据的一条使用记录,所以类似于“文件粉碎机”之类的软件在“粉碎”文件时除了删除文件指针,还会在文件对应的存储区域填入数据来保证文件无法再恢复。软链接类似于Windows系统下的快捷方式,当软链接链接的文件被删除时,软链接也就失效了。

  9. 压缩/解压缩和归档/解归档 - gzip / gunzip / xz / tar

    [root@iZwz97tbgo9lkabnat2lo8Z ~]# wget http://download.redis.io/releases/redis-4.0.10.tar.gz
    --2018-06-20 19:29:59--  http://download.redis.io/releases/redis-4.0.10.tar.gz
    Resolving download.redis.io (download.redis.io)... 109.74.203.151
    Connecting to download.redis.io (download.redis.io)|109.74.203.151|:80... connected.
    HTTP request sent, awaiting response... 200 OK
    Length: 1738465 (1.7M) [application/x-gzip]
    Saving to: ‘redis-4.0.10.tar.gz’
    100%[==================================================>] 1,738,465   70.1KB/s   in 74s
    2018-06-20 19:31:14 (22.9 KB/s) - ‘redis-4.0.10.tar.gz’ saved [1738465/1738465]
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls redis*
    redis-4.0.10.tar.gz
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# gunzip redis-4.0.10.tar.gz
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls redis*
    redis-4.0.10.tar
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# tar -xvf redis-4.0.10.tar
    redis-4.0.10/
    redis-4.0.10/.gitignore
    redis-4.0.10/00-RELEASENOTES
    redis-4.0.10/BUGS
    redis-4.0.10/CONTRIBUTING
    redis-4.0.10/COPYING
    redis-4.0.10/INSTALL
    redis-4.0.10/MANIFESTO
    redis-4.0.10/Makefile
    redis-4.0.10/README.md
    redis-4.0.10/deps/
    redis-4.0.10/deps/Makefile
    redis-4.0.10/deps/README.md
    ...
    [root@iZwz97tbgo9lkabnat2lo8Z ~]# ls redis*
    redis-4.0.10.tar
    redis-4.0.10:
    00-RELEASENOTES  COPYING  Makefile   redis.conf       runtest-sentinel  tests
    BUGS             deps     MANIFESTO  runtest          sentinel.conf     utils
    CONTRIBUTING     INSTALL  README.md  runtest-cluster  src
    
  10. 其他工具 - sort / uniq / diff / tr / cut / paste / file / wc

[root@iZwz97tbgo9lkabnat2lo8Z ~]# cat foo.txt
grape
apple
pitaya
[root@iZwz97tbgo9lkabnat2lo8Z ~]# cat bar.txt
100
200
300
400
[root@iZwz97tbgo9lkabnat2lo8Z ~]# paste foo.txt bar.txt
grape   100
apple   200
pitaya  300
        400
[root@iZwz97tbgo9lkabnat2lo8Z ~]# paste foo.txt bar.txt > hello.txt
[root@iZwz97tbgo9lkabnat2lo8Z ~]# cut -b 4-8 hello.txt
pe      10
le      20
aya     3
0
[root@iZwz97tbgo9lkabnat2lo8Z ~]# cat hello.txt | tr '\t' ','
grape,100
apple,200
pitaya,300
,400
[root@iZwz97tbgo9lkabnat2lo8Z ~]# wget https://www.baidu.com/img/bd_logo1.png
--2018-06-20 18:46:53--  https://www.baidu.com/img/bd_logo1.png
Resolving www.baidu.com (www.baidu.com)... 220.181.111.188, 220.181.112.244
Connecting to www.baidu.com (www.baidu.com)|220.181.111.188|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 7877 (7.7K) [image/png]
Saving to: ‘bd_logo1.png’
100%[==================================================>] 7,877       --.-K/s   in 0s
2018-06-20 18:46:53 (118 MB/s) - ‘bd_logo1.png’ saved [7877/7877][root@iZwz97tbgo9lkabnat2lo8Z ~]# file bd_logo1.png
bd_logo1.png: PNG image data, 540 x 258, 8-bit colormap, non-interlaced
[root@iZwz97tbgo9lkabnat2lo8Z ~]# wc sohu.html
  2979   6355 212527 sohu.html
[root@iZwz97tbgo9lkabnat2lo8Z ~]# wc -l sohu.html
2979 sohu.html

你可能感兴趣的:(Linux系统操作)