Question

Questions

Given this data: drwxr-xr-x 2 asmith staff 4096 Feb 6 19:44 scripts Answer questions 6 through 13.

6. In the line above, what does the d on the extreme left mean or refer to?

7. What does the letter r mean?

8. What does the letter w mean?

9. What does the letter x mean?

10. On what date was the directory in the line above last modified?

11. To whom or what does the leftmost rwx apply?

12. To whom or what does the middle r-x apply?

13. To whom or what does the rightmost r-x apply?

14. If you are in the current directory and wanted to display the name of every file and every line in each of those files where the word calculate occurred, what would you type?

15. Which command displays a calendar of the current month and highlights the current day?

16. If you wanted to display a list of all the processes running on a computer, what command would you use?

17. echo $USER provides the same information as what other command?

18. In a bash script, to what does $1 refer?

19. Let's say we have a variable in script named amount. To what does $amount refer? (Note the $.)

20. The bash statement sum_of_scores=$(($sum_of_scores+$score)) demonstrates which one of the following?
A. No sensible person would use bash to do arithmetic.
B. bash arithmetic expressions are straightforward and simple

Answer 1

Given this data: drwxr-xr-x 2 asmith staff 4096 Feb 6 19:44 scripts

Answer questions 6 through 13.

6. In the line above, what does the d on the extreme left mean or refer to?
Answer: d on the extreme left mean or refer to 'Directory' on Linux machines, which means 'Folder' on Windows machines. Here, the 'scripts' is the directory.

7. What does the letter r mean?
Answer: r means Read permission for the directory.

8. What does the letter w mean?
Answer: w means Write permission for the directory.

9. What does the letter x mean?
Answer: x means Execute permission for the directory.

10. On what date was the directory in the line above last modified?
Answer: The directory in the line above was last modified on 6th of February at Time: 19 hours: 44 minutes PM, in the evening.

11. To whom or what does the leftmost rwx apply?
Answer: The leftmost rwx permissions apply to the Owner or user of the 'scripts' directory who created it and is owned.

12. To whom or what does the middle r-x apply?
Answer: The middle r-x permissions apply to Group of the 'scripts' directory who is owning the directory.

13. To whom or what does the rightmost r-x apply?
Answer: The rightmost r-x permissions apply to the Other users or to the rest of the users in the world for them to only have read and execute permissions on the directory.

15. Which command displays a calendar of the current month and highlights the current day?
Answer: The command is:
cal

It displays the current month's calendar and the current day highlighted.
Answer: The command is:

ps

OR,

top

atop

pgrep

pstree

htop

ps -aux | less

This ps command displays all running processes.

The ps, top, atop, pgrep, pstree, or htop commands.

top command: It lists and updates sorted information about Linux processes.
atop command: It lists the advanced system and process monitor for Linux.
htop command: It is an interactive process viewer in Linux.
pgrep command: Using this command you could look up or signal processes per name and other attributes.
pstree command: This lists a tree of processes.

14. If you are in the current directory and wanted to display the name of every file and every line in each of those files where the word calculate occurred, what would you type?
Answer: grep -r 'calculate' *

The above command is used to search in all files under the current directory recursively using grep -r.

When it is required to search in all the files under the current directory and its subdirectory, -r option is the option to be used.

17. echo $USER provides the same information as what other command?
Answer: The below command provides the same information as echo $USER command.

whoami

It displays the user's name who typed in this command.

18. In a bash script, to what does $1 refer?
Answer: The $1 refers to the positional parameter in a bash script. It is a parameter indicated by one or more digits other than the single digit 0.
It is denoted as:
$N where N consists of a single digit.

It is the argument passed to the script from the command line such as $0, $1, $2, $3 . . .
$1 is the first argument.