What does the following command do? grep −vn “abc” x (A) It will print all of the lines in the file x that match the search string “abc” (B) It will print all of the lines in file x that do not match the search string “abc” (C) It will print total number of lines in the file x that match the search string “abc” (D) It will print the specific line numbers of the file x in which there is a match for string “abc”

What does the following command do? grep −vn “abc” x (A) It will print all of the lines in the file x that match the search string “abc” (B) It will print all of the lines in file x that do not match the search string “abc” (C) It will print total number of lines in the file x that match the search string “abc” (D) It will print the specific line numbers of the file x in which there is a match for string “abc”
by

1 Answer

Answer :

(A) It will print all of the lines in the file x that match the search string “abc”
by

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Description : Consider a program that consists of 8 pages (from 0 to 7) and we have 4 page frames in the physical memory for the pages. The page reference string is :  1 2 3 2 5 6 3 4 6 3 7 3 1 5 3 6 3 4 2 4 3 4 5 ... to fill available page frames with pages): (A) 9 and 6 (B) 10 and 7 (C) 9 and 7 (D) 10 and 6

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Consider the reference string 0 1 2 3 0 1 4 0 1 2 3 4 If FIFO page replacement algorithm is used, then the number of page faults with three page frames and four page frames are .......... and ........... respectively. (A) 10, 9 (B) 9, 9 (C) 10, 10 (D) 9, 10

Description : Consider the reference string 0 1 2 3 0 1 4 0 1 2 3 4 If FIFO page replacement algorithm is used, then the number of page faults with three page frames and four page frames are .......... and ........... respectively. (A) 10, 9 (B) 9, 9 (C) 10, 10 (D) 9, 10

Last Answer : (D) 9, 10

The number of strings of length 4 that are generated by the regular expression (0|∈) 1+2* (3|∈), where | is an alternation character, {+, *} are quantification characters, and ∈ is the null string, is: (A) 08 (B) 10 (C) 11 (D) 12

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Last Answer : (D) 12

Suppose that the virtual Address space has eight pages and physical memory with four page frames. If LRU page replacement algorithm is used, .............. number of page faults occur with the reference string. 0 2 1 3 5 4 6 3 7 4 7 3 3 5 5 3 1 1 1 7 2 3 4 1 (A) 11 (B) 12 (C) 10 (D) 9

Description : Suppose that the virtual Address space has eight pages and physical memory with four page frames. If LRU page replacement algorithm is used, .............. number of page faults occur with the reference string. 0 2 1 3 5 4 6 3 7 4 7 3 3 5 5 3 1 1 1 7 2 3 4 1 (A) 11 (B) 12 (C) 10 (D) 9

Last Answer : (A) 11

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