How to: Change / Setup bash custom prompt (PS1)

Here’s my ZSH prompt. I start by defining a bunch of complicated variables, then actually build the prompt with a much more legible set of instructions.


# Define common and useful things to put in a prompt
typeset -A prc
prc[abbrevpath]='%{${fg[red]}%}%B%45


kirk@mysystem [7:54} ~
:) $


where "kirk@mysystem" is green for normal users and red for root. The time is blue. The current directory is in red, and if it's longer that a set amount, the beginning is replaced with " ... " (so that you always see bottommost directory you're in). The smiley face is ":)" in green if the last command you typed executed correctly, or ":(" in red if it didn't. "$" is black, and if you're root, it's "#" instead.

It packs a lot of useful information into a small area, like who you are, where you are, whether you're root, and whether you can make commands that succeed. If I see too many red frowns, I call it quits for the day.

I think you can do most of this in Bash, too, but I never got that creative.

how to eliminate the hostname on the konsole?
what should i add?

How to change the prompt when access is via ssh, I have tried and don’t find that setting.
Debian

Thank you very much

Steve, you may need to create .shrc file or whichever you’re using under root’s home directory so it gets sourced when you log in or sudo as root.

Balaji,

Use following code

x=$(echo $PS1)
echo $x

As the error message says, the error is on line 7, which appears to be your exit command. If you want to exit with a non-zero return code, use a number without parentheses.

@ SimpleSimon

My answer for question 1:

PS1='${PWD/????????????????????????????*/...${PWD:${#PWD}-25}} '

Note: I used 28 question marks otherwise the … could make the string longer. If you reduce it to 25 then use ${#PWD}-22 in the substring length.

Question 2, answer 1:

I have tried this out but I can’t recommend it. I would recommend anser 2 below. However it is interesting to show what can be done.

You need to look at /etc/termcap for your terminal (xterm) in my case, and at the meaning of the tcap codes in terminfo.

In particular:
sc – save cursor
rc – restore cursor
cm – cursor move
ce – clear to end of line

These can take quite a bit of understanding, but my “cm” is \E[%i%d;%dH which means that in my PS1 that \e[1;1H would move the cursor to the top of the screen (the first number is the row). If there is no %i in the "cm" then numbers start from zero.

My "sc" is \E7
My "rc" is \E8
My "ce" is \E[K

So setting PS1 thus:

PS1='${PWD/????????????????????????????*/...${PWD:${#PWD}-25}} \e7\e[1;1H\w\e[K\e8'


Will write the current directory on the top line of the screen.

Next you need to ensure that the checkwinsize is set.

shopt -s checkwinsize

You might put it in your ".bashrc" . This sets the LINES and COLUMNS variables after every external command.

Now try setting PS1 thus:

PS1='${PWD/????????????????????????????*/...${PWD:${#PWD}-25}} \e7\e[$LINES;1H\w\e[K\e8'

This will write the directory at the bottom left. However, this is not good as using the top line. Once the screen is full, bash and program output will mangle the directory line.

Hence I recommend answer 2.

Question 2, answer 2:

Assuming that you are using a virtual terminal - you can often put the current directory (or other info) into title of the window.

I use bash on Windows/Cygwin and by default PS1 set thus:

PS1='\[\e]0;\w\a\]\n\[\e[32m\]\u@\h \[\e[33m\]\w\[\e[0m\]\n\$ '

This makes the prompt:

user@host directory
$

in pretty colours and puts the current directory in the title for the xterm or ansi console (rxvt or Windows command window). If you use another terminal emulator you may need to find other command codes that do this.

This works well except the newline in the prompt can muck up the editing of very long previous commands. However, if you use the answer to question 1 you could remove it.


PS1='\[\e]0;\w\a\]\n\[\e[32m\]\u@\h \[\e[33m\]'${PWD/????????????????????????????*/...${PWD:${#PWD}-25}}\[\e[0m\]\n\$ '


How can I get the /home rather than ~ ?

irvy — I think Vivek may have misunderstood you. You get the /home rather than the abbreviated ~ path by using $PWD (instead of \w or \W for instance). You shouldn’t have to precede it by \, either. There are examples above. Good luck.

My fully localised prompt:

export PS1="\e[01;33m# \e[01;35m\D{%A %e %B %G %R %Z} \e[00;31m\u\e[01;32m@\e[00;31m\h \e[01;33m\w :\e[00m\n"

It give something like:
# lundi 8 juin 2009 20:15 CEST dom@tuxstudio ~ :


The # at the beginning associated with the final newline make this prompt absolutely perfect to copy and paste stuffs.

how to change the diectory using go function

hii
Thank U for help

@ahmed
Bash treats backslash characters specially in double quoted strings. Try single quotes around the prompt specification
PS1=’[\d \t \u@\h:\w]$ ‘

@Ahmed:
” and ” are different characters, try replacing them using copy/paste.

My PS1 var is:
export PS1=”\u [\W] \$ “

@Ahmed:
You could try copying the character from the ~/.bashrc file itself, for example at lines 5-6:
# If not running interactively, don’t do anything
[ -z "$PS1" ] && return

The double quotes look different on my side and on the site. There are “strait” quotation marks (unicode 0022) and English quotation marks (unicode 201C / 201D). The site converts the first one into the second one.
Maybe try editing the line with another text editor (nano, vi…) and/or copy the quotation marks from the same file, not from the web site.

For unicode characters, check:
http://triggertek.com/r/unicode/0020-007F
http://triggertek.com/r/unicode/2000-206F

my issue is that my screen size is 140 characters. Due to my PS1 config, my command line actually starts in column 23, that leaves 117 characters possible. Whenever I use AIX or Solaris, I can fill the entire line, and then go to the next line and keep going until I hit enter or some limit like 512 or something. What drives me up a wall with linux is that it can only show 25 characters, then shifts left or right. How can I get linux to display the entire command line and quit that 25 character shuffle crap.