Consider the following statements : (a) UNIX provides three types of…
2017
Consider the following statements :
(a) UNIX provides three types of permissions
* Read
* Write
* Execute
(b) UNIX provides three sets of permissions
* permission for owner
* permission for group
* permission for others
Which of the above statement/s is/are true ?
- A.
Only (a)
- B.
Only (b)
- C.
Both (a) and (b)
- D.
Neither (a) nor (b)
Attempted by 53 students.
Show answer & explanation
Correct answer: C
Answer: Both the listed permission types and permission sets are true.
Explanation:
Permission types: read (r), write (w) and execute (x). These bits control what actions are allowed on a file or directory.
Permission sets: owner (the file's user), group (users in the file's group) and others (everyone else). Each set has its own read/write/execute bits.
Numeric representation (octal): read = 4, write = 2, execute = 1. Add the values for each set to get a three-digit mode. For example, rwxr-xr-- maps to 7 (rwx) for owner, 5 (r-x) for group, and 4 (r--) for others, giving 754.