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performance medium Apply octal-special 2 points

Question 9. CSCD240-E1-B

Convert rwsr-xr-x to 4-digit octal including special bits.

Work the drill

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

Ideal answer
4755

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.

0755
Misconception. Missed the setuid bit (4) in the high position.
Remedy. Mnemonic: 4-2-1 for setuid-setgid-sticky, LEFT of the 3-digit mode.
4750
Misconception. Other triad is r-x not --- so last octal is 5 not 0.
Remedy. Walk triad by triad.
0750
Misconception. Both errors: missed setuid AND misread other triad.
Remedy. Layer-by-layer drill on special bits.

Authority mappings

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

DCWF tasks: T0250
KU outcomes: CO-M10-O1
KU topics: CD-OSC-T7
NCAE errors: SMB Read / failure: SMB operation failed: [Errno .SMB Read / partial: SMB operation failed: Failed .SMB Read / failure: SMB operation failed: [Errno .

Course-artifact links

Lectures

  • CSCD240-S26-L06. Permissions part 2: chmod octal + symbolic, directory x bit