21. Question: What is the main purpose of the chmod command in Linux?
Option 1: Change file permissions
Option 2: Create a new directory
Option 3: Display file contents
Option 4: Delete files
Correct Answer: 1
Explanation: The main purpose of the chmod command in Linux is to change file permissions. It allows you to modify the access permissions of files and directories. You can use it to control who can read, write, and execute specific files or directories.
22. Question: In Linux command redirection, what does 2>&1 mean?
Option 1: Redirect standard error (2) and standard output (1) to the same location
Option 2: Redirect standard error (2) to standard output (1)
Option 3: Redirect standard output (1) to standard error (2)
Option 4: Close standard error and standard output
Correct Answer: 1
Explanation: “2>&1” means that standard error (file descriptor 2) and standard output (file descriptor 1) are both redirected to the same location. This is commonly used to capture error messages and regular output during command execution.
23. Question: In file permissions, what does the “s” represent in the permission string “drwxr-sr-x”?
Option 1: Set user or group ID
Option 2: Sticky bit
Option 3: Synchronized access
Option 4: Special permissions
Correct Answer: 1
Explanation: In the permission string “drwxr-sr-x”, the “s” indicates the “set user or group ID” permission. When set on an executable file, it allows the user running the file to temporarily inherit the permissions of the file’s owner or group, depending on whether it is set on the user or group ID.
24. Question: What is the command used to view the system’s scheduled tasks list?
Option 1: crontab -l
Option 2: tasks
Option 3: cronlist
Option 4: schedulelist
Correct Answer: 1
Explanation: The “crontab -l” command is used to view the list of scheduled tasks (cron jobs) on the system. It lists the cron entries for the currently logged-in user. Scheduled tasks are used to automate various processes in a Linux system at specific times or intervals set by the user.
25. Question: To view the command history executed in the terminal, you would use the ____ command.
Option 1: history
Option 2: log
Option 3: list
Option 4: trace
Correct Answer: 1
Explanation: To view the command history executed in the terminal, you would use the “history” command. This command displays a list of previously executed commands, making it easy to rerun or recall commands used in the past.