Right justifying prompt data in bash

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1

Hi,

I have a custom prompt in Bash. However, I would like to further customise it so that it shows me the date and time. However, I would like this new addition to appear on the right side of the terminal window.

The idea behind this is to "visually balance" some data on the right as most of the time the terminal is used from the left.

I hope this make sense. Please let me know if you require further information.

Regards,

vnayak

2

Not sure if such a thing is really possible with Bash.

Interestingly, the zsh shell has the ability to display things on the right hand side of a terminal. You can do the same things as with PS1, and you don't have to worry about typing over it, or it messing up your commands. The variable to set is RPS1.

3

Hi fpmurphy,

Many thanks for the suggestion and your prompt reply. I did find a few resources on the web which may benefit people using the terminal.

These are below:

8 Useful and Interesting Bash Prompts

and

Add a Separator & Time Stamp Between Terminal Commands to Increase Readability

I than mixed the codes I found on these sites together to make something below:

 Fill with minuses
# (this is recalculated every time the prompt is shown in function prompt_command):

fill="--- "
reset_style='\[\033[00m\]'
status_style=$reset_style'\[\033[0;90m\]' # gray color; use 0;37m for lighter color
prompt_style=$reset_style
command_style=$reset_style'\[\033[1;29m\]' # bold black

# Prompt variable:

#PS1="$status_style"'$fill \t\n'"$prompt_style"'${debian_chroot:+($debian_chroot)}\u@\h:\w\$'"$command_style "
PS1='\n\[\e[32;1m\](\[\e[37;1m\]\u\[\e[32;1m\])-(\[\e[37;1m\]jobs:\j\[\e[32;1m\])-(\[\e[37;1m\]\w\[\e[32;1m\])$fill (\t)\n(\[\[\e[37;1m\]! \!\[\e[32;1m\])-> \[\e[0m\]`if [ $? = 0 ]; then echo \[\e[33m\]^_^\[\e[0m\]; else echo \[\e[31m\]O_O\[\e[0m\]; f$

# Reset color for command output
# (this one is invoked every time before a command is executed):

trap 'echo -ne "\033[00m"' DEBUG

function prompt_command {

        # create a $fill of all screen width minus the time string and a space:

        let fillsize=${COLUMNS}-32
        fill=""

        while [ "$fillsize" -gt "0" ]

        do

                fill="-${fill}" # fill with underscores to work on
                let fillsize=${fillsize}-1

        done

        # If this is an xterm set the title to user@host:dir

        case "$TERM" in

                xterm*|rxvt*)
                bname=`basename "${PWD/$HOME/~}"`
                echo -ne "\033]0;${bname}: ${USER}@${HOSTNAME}: ${PWD/$HOME/~}\007"

        ;;
*)
;;
esac
}

PROMPT_COMMAND=prompt_command

I am by no means an expert Bash scripter however, once I started looking at the code I was able to roughly figure out how this worked. Obviously this code be improved upon but this serves my purpose for now.

Many thanks

vnayak