1. Linux related software
xftp: used to transfer files
xshell : used to type commands
Second, the file structure of Linux
windowsThere are drive letters under the system: such as C drive, D drive, etc. LinuxThere is no concept of drive letters, there is only one root directory /, and all files are under it.
Enter the command in the root directory lsto view the files in the root directory:
The color of the files in the root directory is different because the file types are different.
For example: the dark blue ones are ordinary directories , the light blue ones are some executable files or system libraries , and the tmp one with a green background is a temporary directory.
Different colors are determined by Xsell, you can set the color scheme yourself according to the following figure:
3. System files in the root directory
| Table of contents | illustrate | Remark |
|---|---|---|
| bin | Store executable instructions for ordinary users | Ability to perform processing even in single-user mode |
| boot | boot directory | Including the Linux kernel file and the files required for booting |
| dev | Equipment catalog | All hardware devices and peripherals are placed in this device directory |
| etc | Various configuration file directories | Most configuration properties are stored here |
| lib/lib64 | Commonly used dynamic link libraries at boot time | The bin and sbin instructions will also call the corresponding lib library |
| media | Removable device mount directory | Temporary hanging directory like floppy disk, U disk, CD, etc. |
| mnt | User temporarily mounts other file systems | Additional devices can be mounted here, relatively temporarily |
| opt | Third-party software installation directory | Now habitually placed in /usr/local |
| proc | virtual file system | Usually it is a mapping in memory. Pay special attention to deleting data files by mistake, such as DB, as long as the system does not restart, there is still a high probability that the data can be retrieved |
| root | sysadmin home directory | Except root, other users are placed in the /home directory |
| run | System operation is the required file | It was previously prevented from being in /var/run, and later split into a separate /run directory. Regenerate the corresponding directory data after restarting |
| sbin | Administrative commands that only root can run | Similar to bin, but only belongs to the root administrator |
| srv | The data directory that needs to be accessed after the service starts | |
| sys | Virtual file system like proc | Record core system hardware information |
| tmp | Store temporary files directory | All users can read and write this directory |
| usr | application placement directory | |
| was | Store files that are frequently changed during system execution |
In the Linux system, several directories are more important, and you need to be careful not to accidentally delete or change internal files at will.
:/etc As mentioned above, this is the configuration file in the system. If you change a file in this directory, the system may not start.
:/bin, /sbin, /usr/bin, /usr/sbin This is the directory where the system presets the execution files. For example, ls is in the /bin/ls directory.
It is worth mentioning that /bin, /usr/bin are commands for system users (common users except root), while /sbin, /usr/sbin are commands for root.
:/var This is a very important directory. There are many programs running on the system, so each program will have a corresponding log, and these logs will be recorded in this directory, specifically in the /var/log directory. In addition, the mail The default placement of is also here.
4. Basic concepts
1. User type
- Ordinary users: under the root
home - root user
# 在home有一个user 这里就是之前创建的用户
[root@localhost ~]# cd /home
[root@localhost home]# ls
buting
# 使用~回到root目录，使用/是回到根目录下
[root@localhost buting]# cd ~
[root@localhost ~]#
pwd: Indicates to display the current directory
# 切换到另外一个用户
[root@localhost buting]# su buting
[buting@localhost ~]# pwd
/home/buting
2. The command prompts of the root user and ordinary users are different.
The prompt of the ordinary user is $
the prompt of the root user.#
3. cd ~It means to go to the home directory
4. Absolute path and relative path
Absolute path
The path described starting from the / directory is an absolute path, such as:
[root@localhost /]# cd /home/buting
[root@localhost /]# ls /usr
Relative path
The path described from the current location is a relative path, such as:
[root@localhost /]# cd ../../
[root@localhost /]# ls abc/def
5, . and…
. Indicates that the current directory
.. indicates the upper level directory, that is, the parent directory