LCA Shell Scripting & Automation 4

Question 1

Which cron field position specifies the day of the week?

Accepted Answer

Fifth field (0-7, where 0 and 7 = Sunday)

Answer

In a standard crontab, the five fields are minute, hour, day-of-month, month, day-of-week; the fifth field is day-of-week where both 0 and 7 represent Sunday.

Question 2

What does `awk '{print $NF}' file` print?

Accepted Answer

The last field of each line

Answer

`NF` is the built-in awk variable for the number of fields, so `$NF` refers to the last field.

Question 3

Which sed command deletes lines 3 through 7 from a file's output?

Accepted Answer

sed '3,7d' file

Answer

In sed, address ranges use a comma to separate start and end line numbers, followed by the command letter.

Question 4

What is the effect of `chmod +x script.sh` on a script that has no execute bit set?

Accepted Answer

Adds execute permission for owner, group, and others

Answer

Using `+x` without specifying a user class adds execute permission to all three classes: user, group, and other.

Question 5

Which bash substitution removes the longest matching suffix pattern from a variable?

Accepted Answer

${var%%pattern}

Answer

`%%` removes the longest match of the pattern from the end (suffix), while `%` removes the shortest match.

(LCA) Certified Linux Administrator Practice Test

(LCA) Certified Linux Administrator Practice Test

LCA Shell Scripting & Automation 4