User, file and group permissions
Info
Show all groups a user belongs to
groups <user>Show primary groups for user
id <user>Sudo
Perform a command as the super user
sudo <command>Switch users
Switch to specific user
su <user>Switch to root or specific user and load user profile (CTRL + d to exit user mode)
su -
su - <user>Managing users
Create a new user
Change password for active user
File permissions
Change file mode and access control
Permission types
Numerical values
Permission groups
Set permissions with assigment
Set user to rwx, group to rw and other to r
Set u to rwx, group and other to r
Alter some permission with plus and minus
Add write permissions to user group
Remove read and write permission from other group
Add execute for user, remove write for group, remove rwx for other
Use -R to set permissions recursively
Set group to read and write for the directory and all sub files and folders
Set user / group for new files
Set group automatically when creating new files within <dir> via the g+s SETGID (SET Group ID) flag
Remove setting group automatically for new files within <dir> by removing set group flag
Managing groups and owners
List available groups
Modify a user (usermod) and add (-a) them to a group (-G)
Change file group associated with the file permissions
Change file owner
Cleaning up file permissions
Find files with permission set to 777 and change them to default 644
Find directories with permission set to 777 and change them to default 755
Unlock all locked files found under the current directory
Last updated