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performance easy Apply permissions-chmod 2 points

Question 11. CSCD240-E1-A

Change permissions of notes.sh: owner rwx, group rx, other none. Use octal.

Work the drill

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

Ideal answer
chmod 750 notes.sh
Acceptable alternatives: ["chmod 0750 notes.sh"]

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.

chmod 755 notes.sh
Misconception. Forgets "other none" and defaults to r-x for other (5).
Remedy. Explicit: other = 0 when "none" requested. Drill 000-777 flash cards.
chmod 740 notes.sh
Misconception. Drops exec from group (gives r-- = 4 instead of r-x = 5).
Remedy. Remind: group gets r+x = 4+1 = 5 when "read and execute" requested.
chmod u=rwx,g=rx,o= notes.sh
Misconception. Symbolic when question asked for octal.
Remedy. Read the question carefully — "only octal" restricts form.

Authority mappings

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

DCWF roles: IT-451 System Administrator
DCWF tasks: T0136 T0144
KU outcomes: CD-OSC-O4CO-M9-O2
KU topics: CD-CSP-T16
O*NET tasks: SOC 15-1212.00: task 6SOC 15-1212.00: task 7SOC 15-1244.00: task 1SOC 15-1244.00: task 2
NCAE errors: SMB Login / failure: SMB operation failed: [Errno.SMB Read / failure: SMB operation failed: [Errno .WWW Content / failure: Failed to connect to hostWWW Content / timeout: TimeoutWWW Content / failure: Website cannot be reachedSMB 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-L06. Permissions part 2: chmod octal + symbolic, directory x bit

Lab questions

  • CSCD240-S26-LAB3: Convert rwxr-x--- to octal. Convert 644 to rwx.
  • CSCD240-S26-LAB3: chmod 750 file.sh. Then verify with ls -l.

CTF challenges

  • 02 Permissions: Decode 755
  • 02 Permissions: Decode 644
  • 02 Permissions: Decode 700
  • 02 Permissions: Set It Exactly