Can I use this to test if any app is running? Like any random .exe? Maybe there is a better way to ask my question in more detail.

I have a function that runs a shell command. The shell command runs a perl script that creates a text file. The next line in my VB code actually uses the text file. The problem is the perl takes about 45 seconds to run, and the vb continues to the next line immediately after the shell command starts. I want it to wait until the perl finishes running. How do I do that?