Linux fundamentals questions and answers
Filesystem, shell, permissions, processes and useful Linux commands.
These are practice variations, many generated from templates and numeric inputs, not an official question bank. They remain outside search indexing until at least 100 independently reviewed questions across five chapters are available.
Questions and clear answers
01Commands · foundation · Editorial previewWhat does pwd show in a Linux terminal?+
pwd prints the absolute path of the shell's current working directory.
02Commands · foundation · Editorial previewWhat does ls -a show?+
It lists entries including dot-prefixed hidden files, subject to access permissions.
03Permissions · foundation · Editorial previewWhat does chmod 644 mean for a file?+
The owner can read and write, while group and other users have read permission only.
04Safety · foundation · Editorial previewWhy is rm -rf risky?+
It recursively and forcefully deletes files and folders, usually without an easy recycle-bin recovery.
05Permissions · advanced · Editorial previewIn linux — Permissions: A regular file named report-4412.txt is set to chmod 640. Which permissions do group members receive?+
640 means group has read-only permission (4), owner has read and write (6), and others have none (0).
06Shell commands · foundation · Editorial previewIn linux — Shell commands: You are in the Linux shell working in directory /home/student/work-212. Which command displays the absolute current directory?+
pwd prints the shell's current working directory; here it would show /home/student/work-212 if that is the actual directory.
07File paths · foundation · Editorial previewIn linux — File paths: A Linux shell is in /home/student/work-1011. Is /etc/hosts an absolute path or a relative path?+
/etc/hosts is absolute because it begins at the filesystem root /, regardless of the current directory.
08Directory navigation · intermediate · Editorial previewIn linux — Directory navigation: You are in the Linux shell working in directory /home/student/work-1810. Which command displays the absolute current directory?+
pwd prints the shell's current working directory; here it would show /home/student/work-1810 if that is the actual directory.
09Disk storage · foundation · Editorial previewIn linux — Disk storage: A disk storage activity has 2609 files using 8 MB each and 9 MB of extra files. Find total storage.+
Total = 2609 × 8 + 9 = 20881 MB, before filesystem overhead.
10Processes · advanced · Editorial previewIn linux — Processes: A workload performs 3408 independent tasks, each taking 15 seconds sequentially. How many seconds in total?+
Sequential time = 3408 × 15 = 51120 seconds (parallelism not assumed).
11Backups · intermediate · Editorial previewIn linux — Backups: A backup plan covers 4207 GB and a verified copy stores 22 GB. How much has not yet been copied?+
Uncopied amount = 4207 − 22 = 4185 GB (assuming the same units and no duplicate data).
12Memory usage · foundation · Editorial previewIn linux — Memory usage: A device has 5006 MB free memory. Two tasks use 6 MB and 8 MB. How much free memory remains?+
Remaining free memory = 5006 − 6 − 8 = 4992 MB, assuming no other changes.
13Networks · foundation · Editorial previewIn linux — Networks: A networks transfer sends 6448 megabits at a steady 13 megabits/second. Find ideal transfer time.+
Time = size/rate = 6448/13 ≈ 496 seconds, ignoring protocol overhead.
14Package management · intermediate · Editorial previewIn linux — Package management: On Ubuntu, a system has 1605 installed packages. Which APT command refreshes repository indexes without upgrading installed packages?+
sudo apt update refreshes the package indexes; it does not upgrade the 1605 installed packages.
15File operations · advanced · Editorial previewIn linux — File operations: You are in the Linux shell working in directory /home/student/work-2404. Which command displays the absolute current directory?+
pwd prints the shell's current working directory; here it would show /home/student/work-2404 if that is the actual directory.
16Security · foundation · Editorial previewIn linux — Security: An email asks the owner of device 3203 to install a 'security fix' from an unknown link. What should they do?+
Do not install it. Verify updates through the official vendor or operating system, and independently check the sender and domain.
17Permissions · intermediate · Editorial previewIn linux — Permissions: A regular file named report-4002.txt is set to chmod 640. Which permissions do group members receive?+
640 means group has read-only permission (4), owner has read and write (6), and others have none (0).
18Shell commands · foundation · Editorial previewIn linux — Shell commands: You are in the Linux shell working in directory /home/student/work-4801. Which command displays the absolute current directory?+
pwd prints the shell's current working directory; here it would show /home/student/work-4801 if that is the actual directory.
This is an educational practice preview. Answers and board-specific alignment are undergoing editorial review; these are not official exam questions.