Article Directory
1. Linux directory structure
Linux is a tree-shaped directory. The
root directory
-the starting point of all partitions, directories, files, etc.
-In the entire tree-shaped directory structure, a separate "/" is used to indicate
common subdirectories-
/root ;/bin; /boot ;/dev ; /etc-
/home; /var; /usr; /sbin
structure as shown below
| Linux directory | effect |
|---|---|
| /root | Administrator's host (home) directory |
| /home/xxx | Home directory of ordinary users |
| /bin | Command file directory, storing all user executable commands |
| /sbin | Administrator operation directory, storing management commands that can only be executed by the administrator |
| /boot | System kernel, startup file directory |
| /dev | (device) Store device files (CD-ROM, hard disk, etc.) |
| /etc | Store configuration files for system programs and most applications (rpm/yum installation) |
| /where | (Variable) Store files that can be changed, including various log files |
| /lib | (library) The dynamic link shared library file that stores the system program (similar to the DLL file in windows) |
| /usr | Store system user tools and programs |
| /media | Removable media attachment point, such as U disk, CD-ROM, etc. |
| /proc | File to store the information of the mapping system |
| / mnt | Directory for temporarily mounting storage devices |
| /opt | (optional) The directory where the third-party application is installed |
| /tmp | Temporary files stored in the system |
2. View the contents of the file
2.1：cat
Function: directly display the content of the entire file
格式：cat [选项] 文件名
| Options | effect |
|---|---|
| -n | Number all output lines |
| -b | Do not number blank lines |
| -s | Replace all consecutive blank lines with one blank line |
Number all output lines No number
for blank lines
Replace all consecutive blank lines with one blank line
2.2 more
■Full-screen display of file content in pages
格式：more [选项] 文件名
■Interactive operation mode
| Operation method | effect |
|---|---|
| Enter | Scroll down line by line |
| space bar | Scroll down one screen |
| b | Flip up one screen |
| q | drop out |
◆When turning to the last page, it will automatically exit
◆When used in conjunction with pipeline operations (for example: ls -R /etc | more), page up cannot be paged
2.3 less
■Same as the more command, but with more extended functions
格式：less [选项] 文件名
| Operation method | effect |
|---|---|
| Page Up | Page up |
| Page Down | Page down |
| / | Find content |
| n | Next content |
| N | Previous content |
| ↑ | Scroll up |
| ↓ | Scroll down |
| Enter | Scroll down line by line |
| space bar | Scroll down one screen |
| b | Flip up one screen |
| q | drop out |
Contrast the difference between more
◆It will not automatically exit after
turning down to the last page. ◆It can be used in combination with pipe operation to turn pages up.
2.4 head、tail
■head command
Purpose: View part of the content at the beginning of the file (default is 10 lines)
格式：head -n 文件名 （n是行数）
■tail
function: view a small part of the content at the end of the file (the default is 10 lines)
格式：tail -n 文件名
tail -f 文件名 （跟踪文件尾部内容的动态更新）
View the contents of the 5 lines at the beginning of the file, use cat -n to facilitate viewing
3. The content of the statistical file----wc
Function: Count the number of words in the file (word count) and other information
格式：wc [选项] 目标文件
| Options | effect |
|---|---|
| -l | Count the number of rows |
| -w | Count the number of words |
| -c | Count the number of bytes |
If you enter the wc command without any options, the default -lwc three options
are used at the same time
. The first number 14 of the statistics of the bb.txt file here is the number of lines; the second number 15 is the number of words; the third number 36 Is the number of bytes; the fourth is the name of the file
4. Retrieve and filter file content: grep
■Search and display the line including the specified character string in the file
格式：grep [选项] 查找条件 目标文件
| Command options | Description |
|---|---|
| -i | Not case sensitive when searching |
| -v | Display all lines that do not contain matching files (reverse query, reverse matching) |
| -c | Only output the total number of matched rows (not the number of matched rows) |
| -n | Show matching line and line number |
| -e | Realize the matching of multiple search conditions, logical or relationship |
| -E | Support the use of extended regular expressions, which is equivalent to using the egrep command |
| -The | Exact match, which means "match only" |
查找条件设置
–要查找的字符串以双引号括起来
–“^……”表示以……开头，
“……＄”表示以……结尾
“^$”表示空行
示例：grep -ie "^NAME" -e "7$" CentOS-Vault.repo
5.压缩命令：gzip、bzip2
■制作压缩文件、解开压缩文件
压缩格式：
gzip [-9] 文件名
bzip2 [-9] 文件名 （这里的-9是压缩比例，9的压缩比例最高，耗时比前面的长）
这样压缩的文件都带有默认的扩展名分别为“.gz”和“.bz2”，且原始文件不再保留
解压缩格式：
gzip -d .gz格式的压缩文件 等同于 gunzip 文件名.gz
bzip2 -d .bz2格式的压缩文件 等同于 bunzip2 文件名.bz2
6.归档命令：tar
制作归档文件、释放归档文件
tar [选项]... 归档文件名 源文件或目录
tar [选项]... 归档文件名 [-c目标目录]
| 选项 | 作用 |
|---|---|
| -c | 创建.tar格式的包文件 |
| -x | 解开.tar格式的包文件 |
| -C | 解压时指定释放的自标文件夹 |
| -f | 表示使用归档文件 |
| -p | 打包时保留文件及目录的权限 |
| -P | 打包时保留文件及目录的绝对路径 |
| -t | 列表查看包内的文件 |
| -v | 输出详细信息、(Verbose ) |
| -j | 调用bzip2程序进行压缩或解压 |
| -z | 调用gzip 程序进行压缩或解压 |
7.文件编辑器：vi
■文件编辑器的作用
-
创建或修改文本文件
-
维护Linux系统中的各种配置文件
■linux中最常用的文本编辑器 -
vi：类似UNIX操作系统的默认文本编辑器
-
vim：vim是vi文本编辑器的增强版
■三种工作模式：命令模式、输入模式、末行模式
■不同模式之间切换
■命令模式切换至输入模式
| 按键 | 作用 |
|---|---|
| a | 在当前光标位置之后插入内容 |
| i | 在当前光标位置之前插入内容 |
| o | 在光标所在行之下插入一个新行内容 |
| O | 在光标所在行之上插入一个新行内容 |
| A | 在所在行的行尾插入内容 |
| I | 在所在行的行首插入内容 |
命令模式
| 操作类型 | 操作键 | 功能 |
|---|---|---|
| 翻页移动 | Page Down健或Ctrl+F | 向下翻动一整页内容 |
| Page Up键或Ctrl+B | 向上翻动一整页内容 | |
| 行内快速跳转 | Home键或^键、数字0键 | 跳转到本行的行首 |
| End键或$键 | 跳转到本行的行尾 | |
| 行间快速跳转 | 1G或gg | 转到文件内容的第1行 |
| G | 跳转到文件的最后一行 | |
| #G | 跳转到文件中的第#行(其中"#”号用具体数字替换) | |
| M | 跳转至当前页的中间位置 | |
| 显示行号 | : set nu | 在编辑器中显示行号 |
| : set nonu | 取消行号显示 | |
| 删除 | x或Delete键 | 删除光标处的单个字符 |
| dd | 删除当前光标所在行(有剪切功能) | |
| #dd | 删除从光标处开始的#行内容 | |
| d^ | 删除当前光标之前到行首的所有字符 | |
| d$ | 删除当前光标处到行尾的所有字符 | |
| dw | 删除光标处的整个单词 | |
| 替换字符 | R或Shift+r | 替换当前光标处字符 |
| 复制 | yy | 复制当前行整行的内容到剪贴板 |
| #yy | 复制从光标处开始的#行内容 | |
| 粘贴 | p（小写） | 粘贴到光标所在行之下 |
| P（大写） | 粘贴到光标所在行之上 | |
| 查找 | / word | 从当前光标处开始向后进行查找字符串"word" |
| ?word | 从当前光标处开始向前进行查找 | |
| n | 定位下一个匹配的被查找字符串 | |
| N | 定位上一个匹配的被查找字符串 | |
| 撤销 | u | 按一次取消最近的一次操作;重复u键,恢复多步操作 |
| U | 用于取消对当前行所做的所有编辑 | |
| 保存退出 | : w | 保存修改的内容 |
| :w 新文件名 | 另存为其它文件 | |
| :q | ||
| :q! | 放弃对文件内容的修改并退出 | |
| ZZ或:wq、:x | 保存当前的文件内容并退出vi编辑器 | |
| 打开新文件 | :e 其它文件名 | 打开新的文件进行编辑 |
| 读入文件内容 | :r 其它文件名 | 在当前文件中读入其他文件内容 |
| 文件内容替换 | ：s /old/ new | 将当前行中查找到的第一个字符串"old”串替换为"new" |
| ：s /old/ new/ g | 将当前行中查找到的所有字符串 “old”替换为"new” | |
| :#,# s/old/ new/ g | Replace all strings "old" with "new" in the range of line number "#, #" | |
| :% s/old/ new / g | Replace all strings "old" with "new" in the entire file | |
| ：s /old/new/ c | Add the c command at the end of the replacement command, and the user will be prompted for confirmation for each replacement action |