Exam LFCS topic 1 question 116 discussion

The correct answers are: B. chmod +t /tmp D. chmod 4775 /tmp Explanation: The sticky bit is a special permission flag that can be set on directories. When applied to a directory, it modifies the behavior of file deletion within that directory. Specifically, it restricts the deletion of files within the directory to: The owner of the file The owner of the directory The superuser (root) The correct commands: chmod +t /tmp: This uses the symbolic mode to add (+t) the sticky bit to the /tmp directory. chmod 4775 /tmp: This uses the octal mode representation, where 4 corresponds to the sticky bit (1000 in binary), and 775 are the standard permissions for the directory (rwxrwxr-x). Incorrect commands: A. chmod +s /tmp: This sets the setuid bit, not the sticky bit. C. chmod 1775 /tmp: This sets the sticky bit (1) but also the setuid bit (4), which is usually not desired for the /tmp directory. E. chmod 2775 /tmp: This sets the setgid bit (2), not the sticky bit.

B. chmod +t /tmp C. chmod 1775 /tmp The sticky bit is a permission bit that makes a directory such that only the owner of the file within those directories can delete or rename the files. The symbolic method to set the sticky bit is with +t and the octal method is with a leading 1 in the four-digit octal representation.

chmod 1777 dir chmod +t dir

The correct commands to set the sticky bit for the directory /tmp are: C. chmod 1775 /tmp E. chmod 2775 /tmp Both of these commands set the sticky bit on the /tmp directory. The sticky bit is represented by the number 1 in the first digit of the permission mode (i.e., as the most significant bit in the digit). Option A (chmod +s /tmp) sets the setuid (SUID) bit, not the sticky bit. Option B (chmod +t /tmp) is not a valid way to set the sticky bit. Option D (chmod 4775 /tmp) sets the SUID bit and the group-execute permission, but it doesn't set the sticky bit. So, options C and E are the correct ones for setting the sticky bit on the /tmp directory.