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Development Tools Console Foundations Users and Permissions File Permissions

Carlos Lantigua
Carlos Lantigua
5,938 Points

console foundations Quiz Question 2 of 3

Question: Which of the following octal representations is equivalent to the following permission string: -rwxr-x--x

Answer: 751

I am not understanding why this is equal to 751, going by what I learned from the video and teachers note, I am thinking it should be 734.

r = 4, w = 2, x =1

|rwx| |rwx| |rwx|


I am terrible at math so maybe I am missing something, please explain if I am, thank you.

1 Answer

28,556 Points

Let's break the permissions into sections:

  1. User: rwx
  2. Group: r-x
  3. Other: --x

As you state in your post r = 4, w = 2, x = 1 and a lack of permission is 0.

So to calculate the user number it is 4 + 2 + 1, which equals 7. For the group it is 4 + 0 + 1, which equals 5. For other it is 0 + 0 + 1, which equals 1.

Therefore you end up with 751.

Carlos Lantigua
Carlos Lantigua
5,938 Points

Ok I understand it now, its the equivalent of all the numbers in involved in that group. Thank you for the clear explanation.