Bash – Perl script, do cd on terminal

It is an expected behavior. The script is run in a subshell, and cannot change the parent shell working directory. Its effects are lost when it finishes.

To change the current shell's directory permanently you should use the source command, also aliased simply as ., which runs a script in the current shell environment instead of a sub shell.

The following commands are identical:

. script

or

source script

I see three solutions using .last_dir. You can place the echo $PWD > ~/.last_dir either:

1. In a special function that would be a wrapper for cd:

   function cd_
   {
     [[ -d "$@" ]] || return 1
     echo "$@" > ~/.last_dir
     cd "$@"
   }
   

   Place this in your ~/.bashrc and then use cd_ instead of cd every time you want your new working directory to be stored.

2. In your $PROMPT_COMMAND (not recommended):

   PROMPT_COMMAND="$PROMPT_COMMAND; pwd > ~/.last_dir"
   

   You can test this directly from the terminal or place it in ~/.bashrc. This solution, however, triggers a disk write each time the prompt appears, which might cause trouble - but on the other hand, .last_dir would contain the current directory no matter how you got there.

3. In a custom perl extension script for rxvt. I've never created one myself, but you can find quite a few examples on the web.