How to add an unbroken line in bash starting from end of my left hand PS1 text to the right hand side

user3654535

3/20/23, 3:28 AM

I am having trouble wrapping my mind around this little problem

Basically Im using this bash PS1 script because its kinda cool:

PS1="\n \[\033[0;34m\]╭─────\[\033[0;31m\]\[\033[0;37m\]\[\033[41m\] \u \[\033[0m\]\[\033[0;31m\]\[\033[0;34m\]─────\[\033[0;32m\]\[\033[0;30m\]\[\033[42m\] \w \[\033[0m\]\[\033[0;32m\] \n \[\033[0;34m\]╰ \[\033[1;36m\]\$ \[\033[0m\]"

looks like this:

What I want to do is print a time stamp on the right hand side with a solid line connecting the end of the left side to the beginning of the right side of the text, for example:

ben @ local ------------------------------------------12:00pm

I tried doing this:

$(printf '%*s' $COLUMNS  '-')

but that obviously just creates a whole new line filled with the dashes.

How do I get the value of where the curser left off, I see tput sc but I don't understand how to use that in a variable? Then print the lines, leaving maybe 5 characters on the right side for the time.

This is my first foray into bash scripting so forgive my ignorance.

Any help is appreciated

153

0 + 0

command-line

bash

scripts

Score:7

Ubuntu

bac0n

3/20/23, 10:04 AM

First, you have to strip escape sequences from the prompt string and expand it to get the real length to subtract the column length.

prompt_handler(){
    local A="$2[\A]"

    while [[ $A =~ \\[\x1b\\[[0-9\;]*m\\] ]]; do
       A=${A//"${BASH_REMATCH}"}
    done

    A=${A@P} \
    A=$((COLUMNS-${#A}))

    eval printf \
        -v A ─%.s {1..$A}

    PS1="$1$2${A}[\A]$3"
}

PROMPT_COMMAND='prompt_handler "\n" " \[\033[0;34m\]╭─────\[\033[0;31m\]\[\033[0;37m\]\[\033[41m\] \u \[\033[0m\]\[\033[0;31m\]\[\033[0;34m\]─────\[\033[0;32m\]\[\033[0;30m\]\[\033[42m\] \w \[\033[0m\]\[\033[0;32m\]" "\n \[\033[0;34m\]╰ \[\033[1;36m\]\$ \[\033[0m\]"'

0 + 0

terdon

3/20/23, 12:01 PM

This is really neat! It would benefit from some explanation though since you are using various bash features that will not be known by many. I had to look up the `${A@P}`, for instance, to learn that it is a special expansion mode that makes the variable be expanded as though it were a prompt string.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: How to add an unbroken line in bash starting from end of my left hand PS1 text to the right hand side

TH: วิธีเพิ่มบรรทัดที่ไม่ขาดตอนใน bash โดยเริ่มจากส่วนท้ายของข้อความ PS1 ทางซ้ายมือของฉันไปทางขวามือ

RO: Cum să adaug o linie neîntreruptă în bash, începând de la capătul textului PS1 din partea stângă până în partea dreaptă

RU: Как добавить неразрывную строку в bash, начиная с конца моего левого текста PS1 и заканчивая правой стороной

VI: Cách thêm một dòng liền mạch trong bash bắt đầu từ cuối văn bản PS1 bên tay trái của tôi sang phía bên tay phải

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