Open a shell and execute the command

ps -ef | grep bash

Then run your script twice:

up 2
up 2

Rerun the ps command and you will see two more instances of /bin/bash running. Each of these uses resources. Also if you now look at your history, you’ll see that some recent commands are not present.

In order to “fix” this, you’d need to run an exit command for each instance of the up script, which would of course undo the directory change.

The easiest way to make a cd in a script “stick” is to use a “. ” (dot space) before the command. For example,

. myscript

could make cd commands and other environment changes in the script stick after the script exits without spawning a new shell

Also, its generally considered bad form to copy scripts into /bin. Most users I know create a local bin directory under their user account and put their own scripts there. This has the added benefit that all the scripts you create are immune to system upgrades if /home is on a separate partition or you back up user data before upgrading.

I don’t mean to be picky, but new users will look at what you write as gospel. Teaching them bad habits to begin with is not a good way to start.

Regard,
alan