ADV PROG DAY 3

Question 1

When used, returns all the values in the array as a single value. The * can be replaced with an index number to return the value in that element.

Answer 1

${name[*]}

Question 2

When used,returns the number of elements in the array. The * can be replaced with an index number to return the length of that value.

Answer 2

${#name[*]}

Question 3

Stores name of command used to call current program.

Answer 3

$0

Question 4

Stores number of arguments passed to script or function.

Answer 4

$#

Question 5

References all arguments passed to script or function.

Answer 5

$*

Question 6

Stores first nine arguments in incrementing variables passed to script or function.

Answer 6

$1, $2, $3, …$9

Question 7

Stores exit status of previous command.

Answer 7

$?

Question 8

For Bash:

Substitutes variables and escaped characters with their actual values.

Answer 8

Double Quotes “”

Question 9

For Bash:

Makes everything literal so the values of variables are not substituted.

Answer 9

Single Quotes ‘’

Question 10

For Bash:

Used to capture the output of a command. A command enclosed in back quotes is replaced by the STDOUT of that command. Shell variable values are substituted within back quotes.

Answer 10

Back Quotes ` `

Question 11

A script reads a line from the keyboard .

assigns the contents of the input to the variable listed. The following example shows two input styles.

Answer 11

read command

–p allows a double quoted prompt.

Question 12

sorts the contents of a text file, line by line.

Answer 12

sort command

Question 13

provides the ability to evaluate a wide range of arithmetic expressions. It evaluates its arguments as expressions and returns the result.

The spacing in an expression is critical.

Answer 13

expr tool