Cfrgtkky

I'm trying to have a part of my prompt set dynamically by a function, so in my .bashrc I have:

asdf ()

{

    echo -n $(pwd)

}

PS1="u@h:w $(asdf)$ "

Opening a shell gives me what I expect at first:

$ bash

darthbith@server:~/test /home/darthbith/test$

However, when I change directory, the part defined by the function doesn't change:

darthbith@server:~/test /home/darthbith/test$ cd ~/test2

darthbith@server:~/test2 /home/darthbith/test$

My actual goal is to use the git-prompt.sh script to show the branch of my git repository when I'm in one with pretty colors and everything, but the problem is that it never updates the branch name when I change repositories. The trivial example above is the simplest reproduction I could come up with for my question.

The .bashrc lines that I have to integrate the git-prompt script:

source ~/.git-prompt.sh

PS1="[33[01;32m]u@h[33[00m]:[33[01;34m]w[33[00m]$(__git_ps1)$ "

According to Bash prompt Howto:

[21:58:33][giles@nikola:~]$ PS1="[$(date +%H%M)][u@h:w]$ "

[2159][giles@nikola:~]$ ls

bin   mail

[2200][giles@nikola:~]$

It's important to notice the backslash before the dollar sign of the command substitution. Without it, the external command is executed exactly once: when the PS1 string is read into the environment.

When you used $(..) in double-quotes, the shell evaluated the command substitution before assigning to PS1. Thus, PS1 contained only the output, not the command substitution itself. Instead, either use single-quotes, or escape the $, so that the string is passed as-is to PS1, and then evaluated when the prompt is set:

$ PS1='$(pwd) $ '

/tmp $ cd /var

/var $ echo "$PS1"

$(pwd) $ 

Compare:

/var $ PS1="$(pwd) $ "

/var $ echo "$PS1"

a /var $  a

/var $