UNIX for Dummies Questions & Answers

I just want to exit my script in a new directory from a bash shell. Problem is that the script internally changes to the directory I want to move to, however when exits is still in the original directory. Does that make sense?

ie usage: goto null

changing from /usr/bin/xtra/test/test3/

will move to /usr/bin/null/test/test3/


#!/usr/bin/sh
#goto
current_directory=`pwd | cut -f 4 -d "/"`
new_directory=`pwd | sed s=$current_directory=$1=`
cd $new_directory

Help is appreciated. Thanks!

I think it is impossible.
Because when you run your script, you open a new subshell proccess.
To do this in your current subshell proccess, you can put your script in the .profile for example.

Tries to execute it thus:

. ./your_script


Witt

What about using a function?

Put something like this in your .profile or .bash_profile:

goto () {
${PWD%/*/*/*}/${1}/${PWD#/*/*/*/}
}

Then you could be in /usr/bin/xtra/test/test3/, type "goto null", and you'd then be in /usr/bin/null/test/test3/.

u can add this extra line on your script to change directory at the very last syntax should be

cd / = to return to root directory

cd /?whatever directory u want to go back

If it's in a script, simply putting "cd /wherever" at the end will not do anything to change where you're at. A script executes as a child process, which does nothing to affect your environment. The script may change directory, but once it exits, you'll still be where you started.
Try it...

Code:

$cat cd-test.sh
#!/bin/sh
echo "I am in $PWD right now"
cd /usr/bin
echo I am in $PWD now..."

$./cd-test.sh
I am in /home/livinfree right now
I am in /usr/bin now...

$ pwd
/home/livinfree

It may work if you source it, but that might now always be a solution.

$ . ./cd-test.sh

cheers for the reply peoples, very much appreciated for the thoughtful responses.

however I just have a supplementry question for LivinFree: In regards to the function, can you please explain what is happening or point me to a place I can find it? I've never come across functions with the same syntax before in a bourne shell and would like to find out more.

And can it handle any number of directories?



Ok, now that i have tested this command I have a better idea what is happening, however it really isn't what I want.

Only because it doesn't work from any directory level and when it is in the right directory structure I only get something like this

(shakey on prodsrv)/usr/bin/code/training/shakey>goto lib
bash: /usr/bin/lib/training/shakey: is a directory

Although I like the idea of it being in the .bash_profile rather than a script.

Any alternate ideas or can we work from here somewhere?

Thanks

Oops, this was my silly error. The function should read:

Code:

goto () { 
cd ${PWD%/*/*/*}/${1}/${PWD#/*/*/*/} 
}

I forgot the cd in the first example, so it was trying to execute /usr/bin/lib/training/shakey. That's why you were getting the error telling you it was a directory.

Basically, instead of you executing the commands "pwd" and "cut" to find out where you were, and then to cut and paste the path, I tried to use builtin variables and manipulation.

In bash (and some other modern shells), the $PWD variable is automatically set when you change directory. It holds the current working directory. The other junk ( ##/*/ and similar...) is built in variable manipulation.
See this thread for an explanation:
https://www.unix.com/unix-for-advanced-and-expert-users/4542-what-does-means.html?s=

(By the way, the curly braces are needed around the variables with modifiers in them, and are optional for the "normal" ones, like in the above example, the ${1}. It simply protects them, and keeps everything seperate.)

Try variations on some of the examples... it's pretty neat to see what you can do.

And as for it handling a different number of directories, you would have to rewrite it, since this is hard-coded to chop the first two directories, change the third, and chop the thrid and fourth.

If you wanted a more "dynamic", or full featured function, it might be better to write an entire script to handle different situations...

Hope this helps, and please post back with any more questions!