Set bash variable every time directory change

Question

I would like the variable to have my bash shell available, similar to pwd , but equal to the section of the current working directory, and not the whole path.

i.e.,

 $PWD=/a/b/c/d/e/f $PATH_SECT=c/d/e 

I have a prompt that already displays this path, but I would like to update the variable in the environment to this value every time I change the directory.

How can i do this?

Answer 1

You can use the promptcmd function. From man bash we learn that this function is executed just before the prompt is displayed. It is empty by default (or rather undefined).

A simple example:

 promptcmd(){ local p=$(pwd) PATH_SECT=${p/\/a\/b\/} } 

Answer 2

You can use alias and function in .bashrc :

 alias cd="supercd" # call the function function supercd(){ builtin cd " $@ " # original cd PATH_SECT=$(pwd) # or whatever }