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The correct answer is (b) tr ‘|\’‘~-‘ > emp.lst

For explanation I would SAY: The translate (tr) FILTER is used for manipulating individual characters in a LINE. It replaces the first character in the first EXPRESSION with the first character in the second expression.

Right OPTION is (a) -d

For EXPLANATION I would say: By using tr command we can delete the characters from a FILE. To perform this operation, we’ve to use -d option. For EXAMPLE,

The correct choice is (d) -s

For EXPLANATION I WOULD SAY: tr command can ALSO remove multiple consecutive characters from a line by using -s option. This will make the line squeeze from multiple consecutive occurrences of a character to a single character. For example, to squeeze multiple contiguous spaces use the following command:

The correct choice is (c) tr

For explanation: The TRANSLATE (tr) filter is used for manipulating individual characters in a LINE. USUALLY, tr command translates characters using one or TWO compact EXPRESSIONS. The syntax for using tr command is,

Correct CHOICE is (B) -C

Easiest explanation: We can use the -c option with UNIQ command to count the FREQUENCY of occurrence of all lines along with the lines. For example,

The CORRECT choice is (a) -d

The explanation: The -d option when used with UNIQ COMMAND lets US select only ONE copy of duplicate entries. For example,

The correct choice is (b) uniq

To elaborate: When we concatenate or MERGE files, we can encounter the PROBLEM of duplicate entries creeping in. UNIX offers a special command (uniq) which can be USED to handle these duplicate entries. We can ALSO use the sort -U command for doing the same piece of work.

Correct OPTION is (a) True

Easiest explanation: uniq command is USED for locating REPEATED and non-repeated entries. But the most important requirement for using uniq command is, the FILE should be sorted. For EXAMPLE,

The CORRECT option is (a) -m

Explanation: When we USE sort command with multiple FILENAMES as ARGUMENTS, it concatenates all of them and sorts them collectively. -m option usually makes the performance to suffer. For example, to sort three FILES, use the following command:

Right choice is (d) -c

The EXPLANATION is: sort command provides an option with the use of which we can check WHETHER the file has actually been STORED in the default order. For EXAMPLE,

Correct choice is (c) -o

The EXPLANATION: Even THOUGH we can redirect the output of SORT to a file, we can also use its -o OPTION for SPECIFYING the output file. For example,

Right choice is (b) -u

Best explanation: sort provides an option i.e. -u (unique) which lets us remove REPEATED lines from a FILE. We can use this option with sort COMMAND to find unique occurrences in the file. For example,

The correct choice is (b) False

The best explanation: EVEN THOUGH we can redirect the output of SORT to a file, we can also use its -o OPTION for specifying the output file. And the interesting fact is, the name of the input and output file can be same. For EXAMPLE,

The correct CHOICE is (a) -n

Explanation: When SORT COMMAND acts on a numeral, strange THINGS can happen if a file contains only NUMERALS. So we have to use the -n option with sort command. For example,

Right OPTION is (c) -r

Explanation: The sort order can be REVERSED using -r option. For EXAMPLE, the following SEQUENCE REVERSE the order,

Right answer is (B) -t

Easy EXPLANATION: sort COMMAND uses one or more contiguous spaces as the default field separator but we can specify our own field delimiter using the option -t. For example, to PERFORM SORTING using | as the delimiter, use the following command:

Correct answer is (a) True

To elaborate: We can sort on more than one FIELDS i.e. we can provide a secondary KEY to sort. For example, if the primary key is the THIRD field and the secondary key is the second field, then we have to specify for every -k option, where the sort ENDS. This is done in the FOLLOWING manner:

Correct choice is (b) -k

Explanation: sort command PROVIDES an option for SORTING file according to our specified field. For this purpose, we have to use -k along with the field NUMBER (based on which we WANT to perform sorting). For example, to perform sorting on second field (name):

Correct answer is (b) False

Explanation: We can also specify a CHARACTER position within a FIELD to the beginning of sort. For example, if we have to sort salary field then we can specify in the form -K m,N where n is the character position in mth field.

Correct option is (d) ONE or more CONTINUOUS spaces

Best EXPLANATION: Unlike CUT and paste command which uses tab as the default field delimiter, SORT command uses one or more contiguous spaces as the default field separator.

Right option is (B) sort

For explanation: SORTING is the ordering of DATA in ascending or descending order. The sort COMMAND is used for ordering a file. Like cut command, sort also identifies fields and perform sorting on specified fields. To sort any file, just provide the name of the file as an argument with sort command.

Correct CHOICE is (a) True

Explanation: By default, sort reorders lines in ASCII collating sequence i.e. whitespaces first, then NUMERALS, uppercase LETTERS and at LAST lowercase letters. But we can change this default sorting sequence using a certain sequence.

The correct answer is (a) -s

For explanation I would SAY: The -s option joins the LINE in the same way the vi editor’s J does. Using this option on a file containing MULTIPLE lines will JOIN all of these lines into a single one.

The correct option is (a) -d

The explanation: Whatever we’ve cut USING cut command can be pasted BACK using PASTE command. paste command also uses tab as the default field DELIMITER but we can use our own field delimiter using -d option with paste command. For example,

Right option is (b) False

The EXPLANATION is: Like CUT command paste command ALSO USES tab as the DEFAULT field delimiter but we can use our own field delimiter using -d option with paste command.

Correct choice is (a) True

Easy explanation: Whatever we’ve CUT using cut command can be pasted back using paste command. This command is useful when we want to VIEW files side by side by pasting them together. But this command PASTES vertically RATHER than HORIZONTALLY.

Right ANSWER is (b) paste

To explain: WHATEVER we’ve cut using cut command can be pasted BACK using paste command. This command is USEFUL when we want to VIEW files side by side by pasting them together. For example,

Right CHOICE is (a) True

To elaborate: Before using cut command, we have to keep in mind that it is necessary to specify that whether we want to cut fields or COLUMNS. This can be specified using -F and -c OPTION respectively.

The correct answer is (c) -d

To explain: By DEFAULT, the CUT command uses tab as the default delimiter but we can specify our own delimiter using -d OPTION. For example,

The correct answer is (b) tab

The explanation is: To EXTRACT USEFUL data from a file, we use the cut command to cut FIELDS rather than columns. The cut command uses tab as the DEFAULT delimiter to cut fields.

Right choice is (c) -f

For EXPLANATION: Sometimes we need to extract specific fields from a FILE instead of columns. For this purpose, -f option is used with cut command followed by an integer number REPRESENTING the FIELD. For example,

The correct choice is (c) 1-3

Best explanation: cut command is used for cutting specific columns. Cut command uses a SPECIAL feature for selecting a column from the beginning and up to END of a line. For EXAMPLE,

Correct answer is (d) cut

The explanation: To extract SPECIFIC columns from a file, we can use cut command FOLLOWED by -c option and list of COLUMN NUMBERS, delimited by a comma. For example,

Correct answer is (c) -c

The explanation is: tail command supports the -c option followed by a positive integer or just an integer depending on WHETHER the EXTRACTION is performed RELATIVE to the beginning or END of the file. For example,

The correct choice is (c) tail -o+5 emp.lst

Best EXPLANATION: The FIRST COMMAND will PREPARE a file for printing by adding header, footers and formatted text. The command head -N 5 emp.lst will display the first 5 lines of emp.lst while the command tail -3 emp.lst will display the last 3 lines of emp.ls

Correct choice is (a) +

The best explanation: We can also address LINES from the beginning instead of the end. The +count OPTION allows US to do that, where count represents the line number from where the selection should BEGIN. For example,

Correct choice is (a) True

Best explanation: Alike head command we can ALSO USE the -n option with the TAIL command to specify the line COUNT to be DISPLAYED from the end of the file. For example,

Right answer is (b) tail

To explain I would say: Complementing the HEAD COMMAND, the tail command is used to display the END of the file. It provides an additional feature of addressing lines. By default, it DISPLAYS the last ten lines of the file.

The CORRECT option is (b) 10

The best explanation: The head command, as the name suggests DISPLAYS the top of the file. When this command is USED WITHOUT any option, it displays the first ten lines of the file.

The correct choice is (b) HEAD

The explanation: The head command is USED for displaying the top of the file. As the name SUGGESTS, it DISPLAYS the beginning of the file which is specified as an argument to the command. For example,

The correct option is (c) +

Best EXPLANATION: There’s an option available with PR command which lets the user to PRINT from a specific page number. This FUNCTION is performed by prefixing a + with the page number. For example, to print from page number 5, use the following command:

Right option is (b) -n

Easiest EXPLANATION: pr command offers MANY OPTIONS which are USED for producing the output in just the format we need. For example,

-ddouble spaces input

-nnumbers lines, helps in debugging code

-o noffsets lines by n spaces, INCREASES left margin of the page

The correct choice is (a) True

To explain I WOULD SAY: If we are not using the -t option with PR command then we can use the -H option to ADD a header of our choice. This option is followed by the header string. For example,

Correct answer is (C) -t

The explanation is: We can use the -t option with PR COMMAND if we want to suppress the headers and associated which are displayed with the output of pr command. For EXAMPLE,

The correct CHOICE is (b) -k

The best explanation: -k option is USED with pr command (where k is an INTEGER) for printing in k columns. For example, if a file contains a SERIES of 12 numbers then we can divide the output into 3 columns in this way:

Right choice is (a) 5

The explanation is: pr command is used for PREPARING a file for printing by adding suitable headers, FOOTERS and formatted text. It ADDS five lines of margin at the top and five at the bottom. The header shows the date and time of last MODIFICATION of the file along with filename and page number.