useradd example_user = will add user of selected name
passwd example_user = makes it so you can create password for user
groupadd example_group = will create the new group
usermod -aG example_group example_user = this will add user to a selected group
su - example_user = will become that user
chgrp example_group /example_directory = will apply the example_group to the example_directory
chmod = will allow you to change permission for file/directory
chmod g+rwx /example_directory or file = will allow the group permission to read, write, and execute
chomd g-rwx /example_directory or file = will get rid of the ability to read, write, and execute for the group permissions
g = is for group
o = is for other
chomd g-rwx * = all files in current directory will be effected
chomd -v num example_file = will change permissions using binary to decimal
num is decimal number like ‘600’ = for this the owner gets r and w (r+w = 6) and 0 means no permissions for the other sections
read = 100 (binary) = 4
write = 010 (binary) = 2
execute = 001 (binary) = 1
id = shows what groups and uid for logged in user
echo text >> /example_directory/example.txt = will append text to example.txt
echo text > /example_directory/example.txt = will over write text to example.txt and or create file example.txt with text in it
Side notes:
chown example_user example_file = Will change the owner of the file to specified owner
List commands
ls = shows directories in current directory
ls -l /example = will show all the files in directory * drwxr-xr— owner group file/directory name * drwxrw-r— owner group file/directory name * drwx-wxrw- owner group file/directory name
ls -ld /example = listing directory instead of at the file level * example: drwx------ owner group directory name
drwxrwxrwx = who can read write and exicute
first 4 are the owner
next 3 are the group
last 3 are what others can do
drwx------ owner group file/directory name
only the owner would be able to see read write and exicute this file/directory
