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multiple_choice medium Apply umask 2 points

Question 2. CSCD240-E1-C

After umask 027, a newly-created regular file gets which octal?

Work the drill

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

Ideal answer
A: 640

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: 644
Misconception. Default umask of 022 produces 644; umask 027 is different.
Remedy. Compute: 666 - 027 masked = 640. File default permissions subtract umask.
C: 600
Misconception. That would be umask 077.
Remedy. Walk 666 - 027 = 640 bit by bit.
D: 750
Misconception. That is default dir perms under umask 027, not file.
Remedy. Dirs start at 777; files start at 666. Apply umask to each base.

Authority mappings

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

DCWF tasks: T0136
KU outcomes: CD-OSC-O4CO-M10-O1
KU topics: CD-CSP-T16