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The correct option is (a) cmp

The BEST explanation: cmp command is used for comparing two files byte by byte. It displays the first mismatch and its location on the terminal. It does not bother about subsequent mismatches but displays only the first mismatch. As soon as the first DIFFERENCE is found, the command terminates and outputs the LINE and byte in which there is a difference. For example,

The correct choice is (a) -b

The best explanation: mv command RENAMES the destination file if it already exists but when -b is USED, it will add a SUFFIX to the filename. This will SAVE a copy of the original file instead of overwriting it. The default suffix is( ~ ).

Right option is (b) False

Explanation: Every file has an INODE number associated with it which is maintained by the KERNEL. This number is not disturbed even if we rename the file. It remains the same no MATTER how MANY times we rename the file.

The CORRECT CHOICE is (B) mv

Explanation: mv command is used for renaming files. This command does not create a copy of the file, it simply renames it. To rename FILE1 to file2 simply type,

The CORRECT answer is (d) move a group of filesand rename a directory

Best EXPLANATION: Apart from RENAMING files, mv command can also move a group of files to a different directory. For EXAMPLE,

The correct option is (c) it will be overwritten

Easy explanation: If the destination file already EXISTS, then the contents of this file will be overwritten with the contents of a source file. For EXAMPLE, mvfile01dir01. If there already exists a file NAMED dir01, then the contents of dir01 will be overwritten with the contents of file01.

Right answer is (a) True

To elaborate: If the destination FILE specified in the mv COMMAND does not EXISTS it will be simply created. For EXAMPLE, if in the command mvfile1file2, if file2 does not exists then it will be created. Now file1 will be KNOWN as filename ‘file2’.

Correct ANSWER is (C) rm — -file.txt

Easy explanation: To delete a file with filename BEGINNING with a ” – “, we have to use ( — ) i.e. double-dash. ” — ”is USED so that rm command does not misinterpret the filename as an OPTION.

The CORRECT option is (d) -F

The best I can explain: If a file is write-protected, we can REMOVE it forcefully using -f option of rm command. For example,

Correct answer is (a) RM-r

The EXPLANATION: rm COMMAND normally does not REMOVE directories but when it is USED with -r option it does. So if we invoke a command like,

Correct answer is (d) -R and -R

Easy explanation: With -r or -R option, rm performs a recursive walk in the file HIERARCHY and searches for every SUBDIRECTORIES and file within this directory, At each stage, it keeps on deleting everything it FINDS.

The CORRECT choice is (a) -i

Explanation: Like in CP command, -i option is also used with RM command for interactive deletion. The prompts asks the user for confirmation before deleting the FILES.

The correct answer is (a) True

The best explanation: Whether we are ABLE to remove a file depends on the PERMISSIONS ASSOCIATED with the file/directory. So sometime it may happen that permissions of a file won’t ALLOW us to delete it.

Correct option is (B) INFORMATIVE messages

Easiest explanation: CP -v DISPLAYS the informative messages while copying files about what is HAPPENING. For example,

Correct choice is (c) rm *

To explain: To delete all files in a DIRECTORY, use (*) with rm COMMAND. It acts as a meta-character and delete all files WITHOUT displaying any message on the TERMINAL. So use this command cautiously.

Correct option is (a) True

For EXPLANATION: Multiple files can be deleted in a SINGLE go USING rm COMMAND. All we need to do is, provides multiple filenames as arguments to the rm command.

Correct option is (b) rm

Explanation: rm command is used in UNIX to remove one or more files. It operates silently and should be used with caution. The filename of the FILE to be deleted is provided as an ARGUMENT to rm command. For example, FOLLOWING command deletes abd.txt file.

The correct CHOICE is (a) True

The best I can explain: -f option COPIES forcefully when the permissions ASSOCIATED with a file does not allow PERFORMING the operation.

The correct option is (b) -l

Easy explanation: -l option is USED with cp command for LINKING FILES INSTEAD of copying. When one file has more than one FILENAMES, we say that the file has more than one link. This file can be accessed by more than one filename.

Correct OPTION is (a) existing file should not be overwritten

For explanation I would SAY: -n option is used with cp command when we do not WANT to want to overwrite the existing file. It MEANS that if the destination file already EXISTS, then it should not be overwritten.

Right answer is (b) True

The EXPLANATION: We can copy multiple files using a single INVOCATION of cp command. To do so, the LAST name SPECIFIED should be a DIRECTORY. For example,cp file1file2file3dir_one. It will copy all the three files to the directory named dir_one.

Correct option is (a) True

The explanation is: Sometimes it may HAPPEN that we cannot copy a FILE because of the permissions associated with it. For EXAMPLE, If the permissions associated with a file are read-protected then we cannot copy the file.

The CORRECT CHOICE is (a) using -R option

Easy explanation: -R option is used to copy an entire directory structure into another one recursively. Here recursively means that the command can DESCEND a directory and examine all the files in its subdirectories and then it will copy the entire structure. For example,cp-R prog_onenew_prog. It will create a copy of contents of entire directory prog_one to new_prog if new_prog does not exist. OTHERWISE, if new_prog EXISTS as a directory,then the whole structure of prog_one will be copied under new_prog as a subdirectory.

Right option is (b) cp file1

For EXPLANATION: For creating a copy of a file into our CURRENT WORKING directory we use the shorthand NOTATION (.). For example,cp file1.will create a copy of file1 into our current working directory with the same NAME.

The correct ANSWER is (c) cp FILE*directory_one

Easy explanation: For copying multiple files with a common starting name such as (file, FILE001, file.txt, fileone.jpg, file-archive.zip) we use (“*”). An asterisk (“*”) is a wildcard – a special CHARACTER which EXPANDS to match other characters.For example,cp file*directory_one will copy all the files whose name will be starting with ‘file’into‘directory_one’ file.

Correct OPTION is (b) -c

Explanation: In case if there is a strict REQUIREMENT that touch command should not create a new file, we can use the -c option with it. Else if the file already exists then it will do nothing.

The correct choice is (d) create

To explain I would SAY: Touch command changes timestamps. It is ALSO an easy way to create empty files.

The only argument required to be specified with touch command is the filename of the FILE to be CREATED.

Right option is (d) deleting files

For explanation I would SAY: CAT command cannot delete files. It can only be used for viewing file contents, creating a file or appending to an existing file.

Correct choice is (C) CONTENTS of file01 three times successively

For explanation: When multiple filenames are SPECIFIED as arguments with cat COMMAND, it concatenates the contents of all the files specified as arguments and displays the OUTPUT on the terminal.

Right choice is (a) -n

For explanation: cat command SUPPORTS -n option which is USED for displaying FILE CONTENTS along with line number while -v is used for displaying nonprintable ASCII CHARACTERS in the file.

Right ANSWER is (c) >>

To EXPLAIN I WOULD say: cat command overwrites the existing file if we try to create another file with a similar filename as an existing file. To avoid this we can use the >> operator. For EXAMPLE, if file01 already exists and we want to append it, then use the following command:

Correct answer is (a) -v

To elaborate: If the FILE that we WANT to display CONTAINS nonprintable ASCII characters, then to display those characters we use -v option with the cat command. -n option is used for displaying the contents of the file along with line numbers.

Right choice is (c) EXISTING file will be overwritten

For EXPLANATION I WOULD say: As cat command is ALSO used to create files, so if we want to create a file with the same filename which already exists in the DIRECTORY then the existing file will be overwritten.

Right OPTION is (a) >

Explanation: > symbol acts as a redirection symbol and RECORDS the input ENTERED by the user in the specified file. For EXAMPLE,

Right OPTION is (a) True

For explanation: cat, like several other UNIX commands can accept more than ONE FILENAME as arguments. For EXAMPLE,

The correct option is (c) cat

For explanation: cat command is used to DISPLAY the contents of a file. For displaying the contents, simply invoke the cat command with the filename (whose contents are to be DISPLAYED) as an ARGUMENT. For EXAMPLE, if abd.txt file contains “HELLO WORLD” then,