Is this something I need to install ... my OS is Ubuntu

Yes, it is a module so it needs to be installed. If you are on bionic then libproc-processtable-perl is available for the system perl through apt.

Sooner or later you are going to want to use a module which isn't available through apt. For that you can read A Guide to Installing Modules.

In reply to Re^3: Use running system processes and filter them on different ways by hippo
in thread Use running system processes and filter them on different ways by edujs7

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