修改linux shell 提示符

远程登录虚拟机，linux shell提示符为-bash-4.1$
要把这个提示符改掉
 
1、新建~/.bash_profile文件
-bash-4.1$ vi ~/.bash_profile
-bash-4.1$ cat  ~/.bash_profile
cat: /home/hadoop/.bash_profile: No such file or directory
提示 权限不够，不能保存

查看用户
-bash-4.1$ whoami
hadoop

-bash-4.1$ pwd
/home/hadoop

修改权限
-bash-4.1$ sudo chmod 777 /home/hadoop

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.
    #2) Think before you type.
    #3) With great power comes great responsibility.

[sudo] password for hadoop:
hadoop is not in the sudoers file.  This incident will be reported.

2、使用root用户，对/home/hadoop开放访问权限，ok
-bash-4.1$ su
Password:
[root@spark0 hadoop]# sudo chmod 777 /home/hadoop
[root@spark0 hadoop]# exit

3、修改~/.bash_profile文件

-bash-4.1$ vim ~/.bash_profile
加上
export PS1='[\u@\h \W]\$'

4、文件生效
-bash-4.1$ source ~/.bash_profile
 
5、现在的提示符是这样的，ok

-bash-4.1$ source ~/.bash_profile
[hadoop@spark0 ~]$pwd
/home/hadoop
[hadoop@spark0 ~]$cd /home/hadoop
[hadoop@spark0 ~]$ls