Episode 26 — Shell environment essentials: PATH, HOME, PS1, and startup files
Linux+ tests shell environment knowledge because many “command not found” and “works for one user but not another” scenarios are really environment problems. This episode explains the environment as the context that shapes command behavior: PATH controls how executables are found, HOME anchors user-relative paths and config locations, and PS1 influences prompts but also signals which shell and context you are in. You’ll learn how startup files establish this environment at login and at shell launch, and why the order matters when diagnosing inconsistent behavior. The exam skill is being able to infer from symptoms whether a problem is command discovery, permissions, quoting, or a startup file that is modifying variables in unexpected ways.
we apply environment thinking to practical troubleshooting and safe configuration habits. You’ll practice diagnosing cases like a script running fine in a terminal but failing in cron because PATH is minimal, or a command working for root but not for a normal user due to different startup configurations. We also cover best practices that align with exam intent: use absolute paths in automation, limit environment changes to the correct scope, and avoid fragile customizations that break non-interactive shells. Finally, you’ll learn a verification approach: confirm variable values in the current session, identify which startup files applied, and make changes in a way that is reversible and testable across a new session, not just the current one. Produced by BareMetalCyber.com, where you’ll find more cyber audio courses, books, and information to strengthen your educational path. Also, if you want to stay up to date with the latest news, visit DailyCyber.News for a newsletter you can use, and a daily podcast you can commute with.
