剛安裝完的 CentOS，在預設畫面都是顯示目前路徑，並不是完整路徑，在使用上常常要下 pwd 去確認目前的路徑，這部份只要在 /etc/profile 上加上一段指令，之後就會出現完整路徑。

設定方式

使用 vim /etc/profile 進行編輯，在最後一行加入 export PS1='[\u@\h \w]\$ ' 再執行，
source /etc/profile 即可。

[root@localhost ~]$         //顯示當下路徑
[root@localhost ~]$ vim /etc/profile

#/etc/profile
export PS1='[\u@\h \w]\$ '
:wq  //存檔

[root@localhost ~]$ source /etc/profile
[root@localhost /root]$ pwd
/root
[root@localhost /root]$ 

變數說明

\a     an ASCII bell character (07)
\d     the date in "Weekday Month Date" format (e.g., "Tue May 26")
\D{format}
       the format is passed to strftime(3) and the result is inserted into the prompt string; an empty format results in a locale-specific time representation.  The braces are required
\e     an ASCII escape character (033)
\h     the hostname up to the first `.'
\H     the hostname
\j     the number of jobs currently managed by the shell
\l     the basename of the shell's terminal device name
\n     newline
\r     carriage return
\s     the name of the shell, the basename of $0 (the portion following the final slash)
\t     the current time in 24-hour HH:MM:SS format
\T     the current time in 12-hour HH:MM:SS format
\@     the current time in 12-hour am/pm format
\A     the current time in 24-hour HH:MM format
\u     the username of the current user
\v     the version of bash (e.g., 2.00)
\V     the release of bash, version + patch level (e.g., 2.00.0)
\w     the current working directory, with $HOME abbreviated with a tilde (uses the value of the PROMPT_DIRTRIM variable)
\W     the basename of the current working directory, with $HOME abbreviated with a tilde
\!     the history number of this command
\#     the command number of this command
\$     if the effective UID is 0, a #, otherwise a $
\nnn   the character corresponding to the octal number nnn
\\     a backslash
\[     begin a sequence of non-printing characters, which could be used to embed a terminal control sequence into the prompt
\]     end a sequence of non-printing characters

常用變數說明

\u 當前用戶的用戶名
\h 用.分開的第一個主機名稱
\H 完整的主機名稱
\W 當前工作目錄的目錄名，只顯示路徑的最後一個目錄
\w 當前工作目錄的目錄名，顯示完整路徑