linux basic version essays

Files and directories frequently used commands

　　Under the command ls

1. 　　-a: Displays all subdirectories and files in the specified directory and hidden files
2.         -l: Displays details of the file list in a way
3.        -h: displays the file size with the -l

Use wildcards:

 　　*

　　？

　　[] Character set

　　relative path/    

 

　　touch: file does not exist, create a new file.

　　　　　　If there last file modification time will be modified.

　　mkdir -p create folders recursively. Examples: mkdir -pa / b / c / d (single sign can not have the same name and the file folder directory)

 

　　rm: -f force delete a file is deleted there is no prompt is not being given the information.

　　　　　　   -r can delete levels of directories.

 

　　Copy and move files

　　　　tree: a tree structure lists the directory structure.

　　　　　tree -d: only displays the directory tree does not display files.

 

　　　　cp: cp source file destination

　　　　　　-i: copy the same files will be found Tips

　　　　　　-r: Copy the file directory

 

　　　　mv: mv source file destination

　　　　　　

 

　　View the file contents

• more output file contents (split-screen display file contents are more suitable for file content file)
• cat output file contents (see the contents of the file less file)

　　　　cat -b (line number file)

　　　　cat -n (whether empty rows can have line numbers)

 

• 　　grep: ^ $ tail head highlight highlighted

　　echo:> >> Assignment redirected to the specified file

 

NIC configuration and IP:　　

• • 　　If at the end of ping time indicates that the network is open to change if additional instructions are unreasonable network
    
    remote login and copy files:
    　　
    
    
  • ssh username @IP
  • scp username @IP: file name or path to the user name @IP: file name and path.
    Remote copy files:
    
    
    
    
    
    
    
    
  sudo (insufficient permissions on the command line when this command is added to the front of the super user permission to operate)
   
  Free Password
•      Configure public key:
  • • 　　　　ssh-keygen to generate SSH keys all the way round
                   to upload public key to the server (ssh-copy-id -p port use @ remote)
    • 
      Configure alias: append ~ / .ssh / config in
      
      • • 　　Host mac alias name
          
          • • • 　　HostName  ip地址　　User  　  　iteamName
                       Port 　    　22

User Permissions: modify directory permissions (chmod + / -rwx filename | directory name)

Group management terminal command to add groups (groupadd group name) delete the group (groupdel group name) to view the group (cat / etc / group)

User management terminal command useradd -m -g group to add a new user name for the new user Delete user userdel -r username

　　　　　　　　　  id username to see the user's UID and GID information
　　　　　　　　　  whoami front view of a single user login information

　　　　　　　　　  who view information for all users currently logged

usermod main user group setting / additional groups