Unmount from bash script with user in mounted directory?

[Rhone]

I'm working on a bash script for creating ISOs for the downloadable Neverwinter Nights resources and Linux client, including an installation script for the first CD.

I haven't done anything this complex with bash before, though, and I'm running into a little dilemma: Ideally the user would mount the first CD, change to the directory, and run ./setup.sh or whatever. I would like the script to be able to install everything from the first CD, then unmount it and prompt the user to switch to the second CD, then mount that and continue installation. However, I know that umount doesn't like unmounting something if a user is in the mounted directory.

So, how can my script unmount the CD even though a user is in the CD's directory when the script is run? Any help would be appreciated.

[Petyr]

Why not have the script copy a script to the user's home dir, then fork off a process to go and run that script and kill itself.
The forked process then can do the rest of the install then back out from the cddrive, unmount, prompt etc etc etc

Petyr

[Rhone]

Thanks for the response, Petyr. That leaves me with two questions/problems, though....

1) How do I fork a process in bash? Man fork doesn't help, as that seems to be describing a C function. I've done some googling and haven't found anything really helpful.

2) If I do manage to accomplish what you describe, then I no longer have a script running from the CD (good), but there is still a user sitting in the mounted directory. Sure, I can change directories from within the scripts, but that is separate process from the user process that is still sitting in the directory where the user originally ran the script. How do I force the user out?

[Petyr]

[JuddRogers]

If your bash script checks for unmount failing (returning non-zero as I recall), then you can echo a message telling the user to please go back to the original shell and cd to home and then press enter.

You can use something like: