Stage 4 · Lesson 3 of 8
Processes and how to see them
Every running program is a . Each process has an ID number called a PID, an owner, and a parent process that started it. ps aux lists all processes, and ps aux | grep node finds one by name.
top, or the friendlier htop, shows live and memory use. When your laptop fan roars or a is "already in use", a forgotten process is often the cause. Finding a process by name, seeing what it uses and who started it is the first step in most debugging.
Common trapclosing a terminal window and assuming the server you started in it has stopped.
A question to check yourself, an AI practice session and 1 cheat sheet entry come when you add the roadmap to your account. Add it
Resources for this stage
Start with· follow one of these
- BookFreeThe Linux Command Line
William Shotts · Beginner
Its chapters on permissions and processes are the clearest free explanation of this stage
- GuideFreeThe Linux Command Line for Beginners (Ubuntu)
Canonical · Beginner
Includes a short, careful section on the superuser and when to use sudo
Practise
Keep handy
Also worth your time
- roadmap.sh: LinuxGo deeper
See the users, permissions and process management branches of the Linux map