What does the + symbol mean in the following grep regular expression: grep '^d[aei]\+d$' /usr/share/dict/words
Correct Answer: A
The + symbol in a grep regular expression means to match the preceding character or character set one or more times. In other words, it means to repeat the previous element at least once. For example, the regular expression ^d[aei]\+d$ will match any word that starts and ends with d and has one or more of the letters a, e or i in between. Some examples of words that match this pattern are dead, deed, died, daiid, etc. The other options are either incorrect or not applicable. The * symbol means to match the preceding character or character set zero or more times. The ? symbol means to match the preceding character or character set zero or one times. The \+ symbol means to match a literal + symbol, not a repetition modifier. References: * LPIC-1 Exam 101 Objectives, Topic 103: GNU and Unix Commands, 103.3 Perform basic file management * LPIC-1 Linux Administrator 101-500 Exam FAQ, LPIC-1 Exam 101 Objectives, GNU and Unix Commands (Total Weight: 25)
Question 12
Which of the following commands reboots the system when using SysV init? (Choose TWO correct answers.)
Correct Answer: A,D
Question 13
Which chown command changes the ownership to dave and the group to staffon a file named data.txt?
Correct Answer: D
Question 14
Which of the following signals is sent to a process when the key combination Ctrl+Z is pressed on the keyboard?
Correct Answer: B
Question 15
What is true regarding UEFI firmware? (Choose two.)
