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  • 10 examples to customize or change the login prompt using PS1 variable of bash shell in Linux


    After your Linux node boots up and once you enter your username and password, you are provided with a shell prompt which looks something like below
    my-linux-setup:~ #

    When  executing interactively, bash displays the primary prompt PS1 when it is ready to read a command, and the secondary prompt PS2 when it needs more input to complete a command.

    Bash allows these prompt strings to be customized by  inserting a number of backslash-escaped special characters that are decoded as follows:
          \a     an ASCII bell character (07)
          \d     the date in "Weekday Month Date" format (e.g., "Tue May 26")
          \D     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

    There are ways to change this as per your requirement, lets go through some of the examples

    Display only the hostname
    # export PS1='[\h :~]# '

    [my-linux-setup :~]#

    Display only the current working directory
    # export PS1='[\w :~]# '

    [/var/lib :~]#

    Display hostname and current working directory with complete path
    # export PS1='[\h:\w :~]# '

    [my-linux-setup:/var/lib :~]#

    Display hostname and current working directory name
    # export PS1='[\h \W :~]# '

    [my-linux-setup lib :~]# pwd
    /var/lib





    Display username, hostname and current working directory with path
    # export PS1='[\u@\h \w :~]# '

    [root@my-linux-setup /var/lib :~]#

    Display username, hostname and current working directory name
    # export PS1='[\u@\h \W :~]# '

    [root@my-linux-setup lib :~]# pwd
    /var/lib

    Display username, FQDN and current working directory with path
    # export PS1='[\u@\H \w]# '

    [root@my-linux-setup.example /var/lib]#

    Display date along with hostname and username
    # export PS1='[\u@\h \d]# '

    [root@my-linux-setup Sat Feb 10]#



    Display current time with username and hostname
    # export PS1='[\u@\h \A ~]# '

    [root@my-linux-setup 16:20 ~]#
    [root@my-linux-setup 16:22 ~]#
    [root@my-linux-setup 16:24 ~]#
    [root@my-linux-setup 16:26 ~]#

    Display the current shell name along with username and hostname
    # export PS1='[\u@\h \s ~]# '

    [root@my-linux-setup -bash ~]#

    Changed the shell to 'sh'
    [root@my-linux-setup -bash ~]# sh
    [root@my-linux-setup sh ~]#


    Deepak Prasad

    is a techie and an author who is still trying to survive in this IT generation with very little knowledge he has on Linux/Unix, VMware, SAN Storage, Automation, networking etc

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    10 examples to customize or change the login prompt using PS1 variable of bash shell in Linux 10 examples to customize or change the login prompt using PS1 variable of bash shell in Linux Reviewed by Deepak Prasad on Saturday, February 10, 2018 Rating: 5

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