Why would setting the prompt in .bashrc not actually affect the prompt?

Question

I am trying to set my shell prompt by inserting the following line into .bashrc in my home directory:

export PS1="\[\e[01;36m\][\u]\[\e[0m\] \[\e[01;37m\]\W\[\e[0m\] $ "

I save this file and re-open bash, but it doesn't change. When I issue the command echo $PS1, the console shows

\h:\w$

which is the default prompt. I looked around .bashrc and do not see the PS1 environment variable being set anywhere except the line that I inserted shown above.

This works on my local machine, but with my account on a remote server it won't stick. How do I make the custom prompt go into effect?

Thanks!

Answer 1

The problem here is the difference between login and interactive shells. See here for a nice summary.

~/.bashrc is only read when starting an interactive (non-login) shell. When you sshinto a remote machine, you are running a login shell so ~/.bash_profile or ~/.bash_login or ~/.profile (in that order) are read instead. You can check this by running bash after loging on to the remote server, that will start an interactive shell, ~/.bashrc will be read and your modified prompt will appear.

To change the prompt that appears when you ssh, set $PS1 in ~/.bash_profile:

export PS1="\[\e[01;36m\][\u]\[\e[0m\] \[\e[01;37m\]\W\[\e[0m\] $ "

Alternatively, you could call ~/.bashrc from ~/.bash_profile or ~/.profile:

if [ "$BASH" ]; then
  if [ -f ~/.bashrc ]; then
    . ~/.bashrc
  fi
fi

The if [ "$BASH" ]; then is useful when using ~/.profile since it will be read by non-bash shells.