bash shell script
 

I was playing with the following script and it did not produce the expected result.

#! /bin/bash
cd /
echo HELLO


I saw HELLO printed on the screen but my current working directory was not at the root directory. Any idea what went wrong?

The script doesn't run exactly as if you typed in the commands yourself... When it's done, it's returning you to where you were. You can check this by sticking a new line in the script before and after the cd...

echo $PWD

This will print out the current directory the script is in. You will see that it starts in your current directory, then moves to root.

Thanks. I got it.

Is there anyway i can make the change permanent?

Maybe, but I don't know it.

Here are two ideas:

1. "Dot Space" your command: $ . my_script

This will run the script in the current shell. By default your scripts run in a new shell which gets destroyed when it's done. That is why your environment is unchanged.

2. Write an alias for your utility rather than a script. I haven't done this with bash but it works for ksh. Look for 'alias' in the bash man page.

Mark

thanks

The unix source command also does what the dot command does.

For more than one line scripts, shell functions supersedes the alias command.