SQL & PL/SQL

Hi, all!!

I have this PL/SQL script that creates an user and imports a dump-file to it, using the command $imp... .
What I need to know is if there is some way to wait for the end of the OS process to continue the execution of the rest of the script. I mean:

Create user XXX identified by YYY ...
$imp XXX / YYY@instance ... -- this line starts a new OS process
--------- HERE, I WANT TO WAIT FOR THE PROCESS ABOVE TO END ---------
connect XXX / YYY@instance; -- and ONLY THEN this line will be processed.

Is this possible?

Thank's!!