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multiple_choice hard Remember permissions-special 2 points

Question 16. CSCD240-E1-C

What does the sticky bit on a directory do?

Work the drill

Answer on paper or in a terminal before revealing the ideal answer.

Ideal answer
A: Only the file owner (or root) may delete files inside

Misconception bank

Each row below is a plausible wrong answer, the thinking that produces it, and the remedy that corrects the misconception. These are the foundation of the multiple-choice framing and the targeted feedback a student receives after answering.

B: Files inherit directory group
Misconception. That is setgid on a directory, not sticky.
Remedy. 4-2-1 mnemonic: setuid=4, setgid=2, sticky=1.
C: Files are read-only
Misconception. Not what sticky does; read-only comes from the file perms.
Remedy. Sticky applies to DELETION permission in a shared dir.
D: Files auto-delete on reboot
Misconception. Unrelated; that is /tmp behavior via systemd-tmpfiles.
Remedy. Separate mechanism.

Authority mappings

Hover any chip for the mapping justification; click to open the authority record.

DCWF tasks: T0136
KU outcomes: CD-OSC-O4
KU topics: CD-OSC-T7
NCAE errors: SMB Login / failure: SMB operation failed: [Errno.SMB Read / failure: SMB operation failed: [Errno .SMB Read / partial: SMB operation failed: Failed .SMB Login / failure: SMB operation failed: [Errno.SMB Read / failure: SMB operation failed: [Errno .SMB Login / failure: SMB connection failed: proto.

Course-artifact links

Lectures

  • CSCD240-S26-L05. Permissions part 1: ls -l anatomy, rwx, file types