find files
The find command is very powerful and is usually used to find files that meet the conditions
If the path is omitted, it means to search in the current folder
soft link
Notice:
1. A hard link file is created without the -s option
Two files occupy the same amount of hard disk space, and hard links to files are hardly established during work
2. The source file should use an absolute path instead of a relative path, so that it can still be used normally after moving the linked file.
Schematic diagram of file soft and hard links
In Linux, file names and file data are stored separately
hint:
In Linux, only files with hardlink count == 0 will be deleted
Use ls -l to see the number of hard links to a file
In day-to-day work, hard links to files are rarely established
Pack and compress
Packing and compression is a way of backing up files in daily work
In different operating systems, the commonly used packaging and compression methods are different
Windows commonly used rar
Mac commonly used zip
Linux commonly used tar.gz
pack/unpack
tar is the most commonly used backup tool in Linux . This command can package a series of files into a large folder, and can also restore a packaged large file into a series of files
The command format of tar is as follows:
Description of tar options:
Note: the f option must be placed at the end, the order of other options can be arbitrary
compress/decompress
gzip
The combination of tar and gzip commands can be used to package and compress files
tar is only responsible for packaging files, but not compression
Use gzip to compress the tar-packed file, and its extension is generally xxx.tar.gz
In Linux, the most common compressed file format is xxx.tar.gz
There is an option -z in the tar command to call gzip, so that the functions of compression and decompression can be easily realized
The command format is as follows:
bzip2
tar can be used in combination with the bzip2 command to package and compress files (same usage as gzip)
tar is only responsible for packaging files, but not compression
Use bzip2 to compress the tar-packed file, and its extension is generally xxx.tar.bz2
There is an option -j in the tar command to call bzip2, which can facilitate the implementation of compression and decompression functions
The command format is as follows:
Software Installation
Install/uninstall software via apt
apt is Advanced Packaging Tool, an installation package management tool under Ubuntu
Most software installations/updates/uninstalls are done using the apt command
Enter apt directly in the terminal to view the help information of the command
Commonly used commands are as follows:
1. Install the software
$ sudo apt install software name
2. Uninstall the software
$ sudo apt remove softwarename
3. Update the list of available packages
$ sudo apt update
4. Update installed packages
$ sudo apt upgrade
5. Dependencies between associated software
$ sudo apt -f install
deb installation format
deb is the installation format of Debian Linux, which can also be used in ubuntu. To install the deb installation package, you need to use the terminal command dpkg. The command format is as follows:
$ sudo dpkg -i <package.deb>
Configure software sources
If you want to install software in ubuntu faster, you can provide software download/installation services by setting the mirror source and selecting a server with faster access to the Internet
The so-called mirror source means that the content of all servers is the same (mirror), but depending on the location, the domestic server is usually faster!
