useradd, userdel, usedmod, users: refresh page (#7661)

pages/linux/usermod.md

@@ -1,16 +1,25 @@
 # usermod
 
 > Modifies a user account.
+> See also: `users`, `useradd`, `userdel`.
 > More information: <https://manned.org/usermod>.
 
-- Change a user's name:
+- Change a username:
 
-`usermod -l {{newname}} {{user}}`
+`sudo usermod --login {{new_username}} {{username}}`
 
-- Add user to supplementary groups (mind the whitespace):
+- Change a user id:
 
-`usermod -a -G {{group1,group2}} {{user}}`
+`sudo usermod --uid {{id}} {{username}}`
 
-- Create a new home directory for a user and move their files to it:
+- Change a user shell:
 
-`usermod -m -d {{path/to/home}} {{user}}`
+`sudo usermod --shell {{path/to/shell}} {{username}}`
+
+- Add a user to supplementary groups (mind the lack of whitespace):
+
+`sudo usermod --append --groups {{group1,group2,...}} {{username}}`
+
+- Change a user home directory:
+
+`sudo usermod --move-home --home {{path/to/new_home}} {{username}}`