Why does Debian host decide to ignore PS1 variable?

Daws · 05-28-2006, 06:04 PM

Hi, this is not a major issue, so please don't spend an undue amount of time on it. This is just something that has confused me in the past and still now. I am just wondering whether anybody else has noticed this and knows why.

Basically when setting up the build environment for the lfs user PS1 is set to "\u:\w\$ "
One day I suddenly thought wait a minute that should mean the prompt reads "username":"working directory"$ ... But it didnt... It was still the default Debian prompt ie "username"@"hostname":"working directory"$

Typing echo $PS1 showed: ${debian_chroot:+($debian_chroot)}\u@\h:\w\$

I know PS1 isnt amazingly important while building the toolchain, but it did lead me to wonder whether any other Debian related stuff was leaking into my supposedly "clean" environment.

Any thoughts?

320mb · 06-11-2006, 10:12 PM

well it appears your system is reading the default PS1 from /etc/profile--
so each user can customize their own PS1, there should be a .bash_profile in the users /home directory.......this is my .bash_profile

Code:

# ~/.bash_profile: executed by bash(1) for login shells.
# I keep this file simple and put everything in ~/.bashrc

# Sets the default permissions for files. 755 for directories 
and 644 for files.
umask 022

# include the configurations from ~/.bashrc 
if [ -f ~/.bashrc ]; then
    source ~/.bashrc
fi

export PATH=$PATH:/usr/X11R6/bin  
export PKG_CONFIG_PATH=/usr/X11R6/lib/pkgconfig 
export PATH=$PATH:/opt/kde/bin

my .bashrc contains the following as well as other configuration stuff

Code:

# Color Variables for Prompt
GRAD1='\333\262\261\260'
GRAD2='\260\261\262\333'
YLOBRN='\[\033[01;33;43m\]'
WHTBRN='\[\033[01;37;43m\]'
REDBRN='\[\033[01;31;43m\]'
BLUBRN='\[\033[01;34;43m\]'
GRNBRN='\[\033[00;32;43m\]'
REDBLK='\[\033[00;31;40m\]'
PPLBLK='\[\033[01;35;40m\]'
WHTBLK='\[\033[01;37;40m\]'
NONE='\[\033[00m\]'
HBLK='\[\033[00;30;30m\]'
HBLU='\[\033[01;34;34m\]'

BLU='\[\033[01;34m\]'
YEL='\[\033[01;33m\]'
WHT='\[\033[01;37m\]'
PRPL='\[\033[00;35m\]'
RED='\[\033[01;31m\]'
GRN='\[\033[01;32m\]'          
GRAY='\[\033[01;30m\]'
PINK='\[\033[01;35m\]'
NORM='\[\033[01;00;0m\]'
CYAN='\[\033[01;36m\]'


export GRAD1 GRAD2 YLOBRN WHTBRN REDBRN
BLUBRN GRNBRN REDBLK PPLBLK WHTBLK NONE 
HBLK HBLU BLU YEL WHT PRPL RED GRN GRAY 
PINK NORM CYAN

PS1="$CYAN[\s]$YEL[\t] $GRN\u$YEL@$BLU\h $WHT[\w]\$$NONE $NORM"

this makes for an easy to change colorful prompt.......

Daws · 06-13-2006, 07:02 PM

Hi, thank you for replying and I am sorry for not replying sooner I'd actually forgotten I'd posted this, its been a while...

Anyway, back to the matter at hand this is the ~/.bash_profile for the "lfs" user

Code:

exec env -i HOME=$HOME TERM=$TERM PS1='\u:\w\$ ' /bin/bash

and this is the ~./bashrc

Code:

set +h
umask 022
LFS=/mnt/lfs
LC_ALL=POSIX
PATH=/tools/bin:/bin:/usr/bin
export LFS LC_ALL PATH

yet despite the presence of these files I still get the wrong PS1...meh I don't think its very important anyway

PS thanks for showing me how to change the colours of the CLI, the idea had never really crossed my mind before now

whereswaldon · 04-10-2018, 06:55 PM

I'll post here for posterity, as I'm sure that nobody is really expecting an answer at this point. Based on the Debian man pages for bash, the reason that PS1 is polluted by Debian is:

Quote:

When an interactive shell that is not a login shell is started, bash reads and exe-
cutes commands from /etc/bash.bashrc and ~/.bashrc, if these files exist. This may
be inhibited by using the --norc option. The --rcfile file option will force bash
to read and execute commands from file instead of /etc/bash.bashrc and ~/.bashrc.

It seems like you should be able to tweak the LFS ~/.bash_profile to use the --rcfile flag to fix this, but I haven't been able to make that work. However, using the --norc flag does prevent the PS1 value from being polluted. You then have to manually

Code:

$ source ~/.bashrc

in order to make sure all of the environment variables are set properly.

If anyone can explain why setting --rcfile /home/lfs/.bashrc still sources /etc/bash.bashrc, I'd be very grateful.