2.7.1

Question 1

_____________ is data that is typically streamed from the keyboard. If a bash command accepts input, by default, it is gathered from stdin.

Answer 1

Standard input (stdin)

Question 2

________________ is data that is typically streamed to the console screen. By default, bash commands send their output to stdout.

Answer 2

Standard output (stdout)

Question 3

_____________ is data that is also typically streamed to the console screen. If a command needs to output an error messages or give diagnostics, by default, it sends this output to stderr.

Answer 3

Standard error (stderr)

Question 4

A Linux pipe is represented by a

Answer 4

vertical bar (|).

Question 5

The pipe functionality is similar to that of using stdout redirection to write the output of one command to an intermediate file that is then used as input to a _______________ using stdin redirection.

Answer 5

second command

Question 6

A plumbing pipe, where water enters from one end and exits the other, can be used as a mnemonic to help explain how the pipe (|)

Answer 6

Operator works.

Question 7

The output from a command is piped to the

Answer 7

tee command.

Question 8

The file used to store the output is added as a tee command __________

Answer 8

argument.

Question 9

A plumbing tee, where water flow is divided from one pipe to two separate pipes, can help you understand how the tee command________

Answer 9

works.

Question 10

__________ are file-like access point to hardware devices.

Answer 10

Device files

Question 11

There are two __________that are often used with redirection and piping. /dev/tty and /dev/null.

Answer 11

device files

Question 12

A _________ is a block of text that is redirected as input to a command

Answer 12

here document

Question 13

Here documents are often used in ________ scripts.

Answer 13

shell

Question 14

Command substitution is implemented using the ____________ operator.

Answer 14

$()

Question 15

When the shell’s command line interpreter encounters the $() operator:

Answer 15

The shell creates a child process that runs the command specified.

The stdout from this first command is redirected back to the shell.

The shell parses the output from the first command into words separated by white space

The shell creates a new command by substituting the parsed output from the first command in place of the $() operator.

The shell creates another child process that runs the second command.