1.新建一個新的用戶user2

sudo adduser temporary

sudo adduser temporary sudo

2.從user1 logout。進入新建用戶user2，修改user1的名字和home目錄名

sudo usermod -l new_username -d /home/new_username -m user1

3.從user2中logout，進入user1(new_username)，刪除user2.

sudo deluser temporary
sudo rm -r /home/temporary

usermod -l new_username -d /home/new_username -m old_username
 
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ubuntu修改用戶名並修改home對應的目錄名