Linux Permissions 5

Question 1

What does the command 'chmod +t /shared' do?

Accepted Answer

Sets the sticky bit on the /shared directory

Answer

The +t flag in chmod sets the sticky bit on a directory, restricting file deletion to file owners only.

Question 2

Which file stores the default umask for all users on a system-wide basis on most Linux distributions?

Accepted Answer

/etc/profile or /etc/bashrc

Answer

System-wide umask settings are typically configured in /etc/profile or /etc/bashrc (or /etc/bash.bashrc on Debian-based systems).

Question 3

A directory has permissions drwxr-x---. Which users can list its contents?

Accepted Answer

The owner and members of the directory's group

Answer

Read permission (r) on a directory allows listing its contents; both the owner (rwx) and group members (r-x) have this, but others (---) do not.

Question 4

What happens when you run chmod u=rwx,g=rx,o= file.txt?

Accepted Answer

Owner gets rwx, group gets r-x, others get no permissions

Answer

The = operator sets permissions exactly; u=rwx gives owner full access, g=rx gives group read+execute, and o= removes all permissions from others.

Question 5

Which special permission bit, when set on an executable file, causes it to run with the privileges of the file's group?

Accepted Answer

setgid bit

Answer

The setgid bit on an executable causes it to run with the effective GID of the file's group rather than the caller's GID.

Linux Practice Test