Ubuntu Unleashed 2015 Edition: Covering 14.10 and 15.04, Tenth Edition

Listing Processes with ps

The ps command lists processes and gives you an extraordinary amount of control over its operation. A process is any running program or instance of a running program. There can be many copies of the same program running at the same time, and when that happens, each will have its own process. Every process has its own address space, or designated part of the computer’s memory that is reserved just for this process and its needs. A process group is created when any process begins and will include that process and any processes started by it.

In the Unix/Linux world, a process (parent) has the ability to create another process (child) that executes some given code independently. This can be really useful for programs that ...