Libro T9 - Writing Scripts, Configuring Email, and Using Databases

Frage 1 von 20

1

Which environment variable stores the format for the command prompt?

Wähle eine der folgenden:

A. PROMPT
B. PSI
C. PAGER
D. PS1
E. None of these variables store the format for the command prompt.

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Frage 2 von 20

1

You want to create a shortcut command for the command cd ~/papers/trade. Which of
the following lines, if entered in a bash startup script, will accomplish this goal?

Wähle eine der folgenden:

A. alias cdpt='cd ~/papers/trade'
B. export cdpt='cd ~/papers/trade'
C. alias cdpt 'cd ~/papers/trade'
D. alias cd 'cdpt ~/papers/trade'
E. env cdpt `cd ~/papers/trade`

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Frage 3 von 20

1

What is the purpose of the EDITOR environment variable?

Wähle eine der folgenden:

A. If it’s set to Y (the default), the shell environment permits editing of commands; if it’s
set to N, such editing is disallowed.
B. It specifies the filename of the text editor that bash uses by default while you’re entering commands at its prompt.
C. If you type edit filename at a command prompt, the program specified by EDITOR
will be launched.
D. If it’s set to GUI, programs call a GUI editor; if it’s set to TEXT, programs call a textbased editor.
E. Some programs refer to EDITOR to determine what external editor to launch when they
need to launch one.

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Frage 4 von 20

1

In what environment variable is the current working directory stored?

Wähle eine der folgenden:

A. PATH
B. CWD
C. PWD
D. PRESENT
E. WORKING

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Frage 5 von 20

1

If typed in a bash shell, which of the following commands will create an environment variable called MYVAR with the contents mystuff that will be accessible to any created subshells?
(Choose all that apply.)

Wähle eine oder mehr der folgenden:

A. export MYVAR='mystuff'
B. MYVAR='mystuff'
C. MYVAR='mystuff'; export MYVAR
D. echo $MYVAR mystuff
E. setenv MYVAR mystuff

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Frage 6 von 20

1

What file might a user modify to alter their own bash environment?

Wähle eine der folgenden:

A. /etc/inputrc
B. /etc/bashrc
C. $HOME/bashrc
D. $HOME/.profile_bash
E. ~/.bashrc

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Frage 7 von 20

1

What commands might you use (along with appropriate options) to learn the value of a
specific environment variable? (Select two.)

Wähle eine oder mehr der folgenden:

A. env
B. DISPLAY
C. export
D. echo
E. cat

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Frage 8 von 20

1

Immediately after creating a shell script called a_script.sh in a text editor, which method
will not work to run the script?

Wähle eine der folgenden:

A. Typing bash a_script.sh at the command line.
B. Typing ./a_script.sh at the command line.
C. Typing . a_script.sh at the command line.
D. Typing source a_script.sh at the command line.
E. Any of the above will work.

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Frage 9 von 20

1

Describe the effect of the following short script, cp1.sh, if it’s called as cp1.sh big.c
big.cc:
#!/bin/bash
cp $2 $1

Wähle eine der folgenden:

A. It has the same effect as the cp command—copying the contents of big.c to big.cc.
B. It compiles the C program big.c and calls the result big.cc.
C. It copies the contents of big.cc to big.c, eliminating the old big.c.
D. It converts the C program big.c into a C++ program called big.cc.
E. It interprets the big.c and big.cc files as bash scripts.

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Frage 10 von 20

1

Where are the commands iterated by the loop located within the loop?

Wähle eine der folgenden:

A. Within the then statement section
B. Between the double semicolons (;;)
C. Within the case and esac constructs
D. Within the test statement
E. Between do and done constructs

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Frage 11 von 20

1

Which of the following lines identify valid shell scripts on a normally configured system?
(Select two.)

Wähle eine oder mehr der folgenden:

A. #!/bin/script
B. #!/bin/bash
C. #!/bin/tcsh
D. !#/bin/sh
E. !#/bin/zsh

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Frage 12 von 20

1

Which of the following are valid looping statements in bash shell scripting? (Select all that apply.)

Wähle eine oder mehr der folgenden:

A. for
B. while
C. if-then
D. until
E. case

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Frage 13 von 20

1

Your SMTP email server receives a message addressed to postmaster. The postmaster
username has an alias of john on this computer. Assuming that the system is properly configured, who will receive the email message?

Wähle eine der folgenden:

A. postmaster
B. john
C. The account listed in ~/.forward
D. root
E. No user, because an alias was set

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Frage 14 von 20

1

Which of the following is not a popular SMTP server for Linux?

Wähle eine der folgenden:

A. Postfix
B. Sendmail
C. Fetchmail
D. Exim
E. qmail

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Frage 15 von 20

1

You see the following line in a script:
mail -s "Error" -c abort < /tmp/msg root
What is the effect of this line, if and when it executes?

Wähle eine der folgenden:

A. An email is sent to the user Error, the script is aborted using root privileges, and error
messages are written to /tmp/msg.
B. An email with the subject of Error and the contents from /tmp/msg is sent to the local
users root and abort.
C. An email with the subject of Error and the contents of /tmp/msg is sent to the local
user root, and then the script is aborted.
D. An email is sent with Error priority to the local user root, and the email system is
then shut down with error messages being stored in /tmp/msg.
E. An email with the subject of Error and contents of /tmp/msg is sent to root, and
information on this is logged with priority abort.

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Frage 16 von 20

1

Your Internet connection has gone down for several hours. What command can you use to
check if there is a long list of jobs in the email queue?

Wähle eine der folgenden:

A. service sendmail status
B. lp -d queue ~/Maildir
C. sendmail -bq
D. mailq
E. ls /var/spool

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Frage 17 von 20

1

You examine your /etc/aliases file and find that it contains the following line:
root: jody
What can you conclude from this?

Wähle eine der folgenden:

A. Email addressed to jody on this system will be sent to the local user root.
B. Email addressed to root on this system will be sent to the local user jody.
C. The local user jody has broken into the system and has acquired root privileges.
D. The local user jody has permission to read email directly from root’s mail queue.
E. The administrator may log in using either username: root or jody.

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Frage 18 von 20

1

You’ve just installed MySQL and run it by typing mysql. How would you create a database
called fish to store data on different varieties of fish?

Wähle eine der folgenden:

A. Type NEW DATABASE fish; at the mysql> prompt.
B. Type CREATE DATABASE fish; at the mysql> prompt.
C. Type NEW DATABASE FISH; at the mysql> prompt.
D. Type DATABASE CREATE fish; at the mysql> prompt.
E. Type DB CREATE fish; at the mysql> prompt.

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Frage 19 von 20

1

Which of the following are true statements about SQL tables? (Select two.)

Wähle eine oder mehr der folgenden:

A. Multiple tables may exist in a single SQL database.
B. Tables may be combined for cross-table searches using the DROP command.
C. Tables consist of rows, each of which holds attributes, and columns, each of which
defines a specific database item.
D. Careful table design can reduce the amount of data entry and database storage size.
E. Tables are stored on disk using a lossy compression algorithm.

Erklärung

Frage 20 von 20

1

What is the effect of the following SQL command, assuming the various names and
data exist?
mysql> UPDATE stars SET magnitude=2.25 WHERE starname='Mintaka';

Wähle eine der folgenden:

A. It returns database entries from the stars table for all stars with magnitude of 2.25
and starname of Mintaka.
B. It sets the value of the stars field in the magnitude set to Mintaka, using a precision
of 2.25.
C. It sets the value of the magnitude field to 2.25 for any item in the stars table with the
starname value of Mintaka.
D. It combines the stars and magnitude=2.25 tables, returning all items for which the
starname is Mintaka.
E. It updates the stars database, creating a new entry with a starname value of Mintaka
and a magnitude of 2.25.

	Erstellt von Victor Rodriguez vor mehr als 7 Jahre

105.1 Customize and use the shell environment 105.2 Customize or write simple scripts 105.3 SQL data management 108.3 Mail Transfer Agent (MTA) basics

Libro T9 - Writing Scripts, Configuring Email, and Using Databases

Frage 1 von 20

Which environment variable stores the format for the command prompt?

Wähle eine der folgenden:

Erklärung

Frage 2 von 20

You want to create a shortcut command for the command cd ~/papers/trade. Which of the following lines, if entered in a bash startup script, will accomplish this goal?

Wähle eine der folgenden:

Erklärung

Frage 3 von 20

What is the purpose of the EDITOR environment variable?

Wähle eine der folgenden:

Erklärung

Frage 4 von 20

In what environment variable is the current working directory stored?

Wähle eine der folgenden:

Erklärung

Frage 5 von 20

If typed in a bash shell, which of the following commands will create an environment variable called MYVAR with the contents mystuff that will be accessible to any created subshells? (Choose all that apply.)

Wähle eine oder mehr der folgenden:

Erklärung

Frage 6 von 20

What file might a user modify to alter their own bash environment?

Wähle eine der folgenden:

Erklärung

Frage 7 von 20

What commands might you use (along with appropriate options) to learn the value of a specific environment variable? (Select two.)

Wähle eine oder mehr der folgenden:

Erklärung

Frage 8 von 20

Immediately after creating a shell script called a_script.sh in a text editor, which method will not work to run the script?

Wähle eine der folgenden:

Erklärung

Frage 9 von 20

Describe the effect of the following short script, cp1.sh, if it’s called as cp1.sh big.c big.cc: #!/bin/bash cp $2 $1

Wähle eine der folgenden:

Erklärung

Frage 10 von 20

Where are the commands iterated by the loop located within the loop?

Wähle eine der folgenden:

Erklärung

Frage 11 von 20

Which of the following lines identify valid shell scripts on a normally configured system? (Select two.)

Wähle eine oder mehr der folgenden:

Erklärung

Frage 12 von 20

Which of the following are valid looping statements in bash shell scripting? (Select all that apply.)

Wähle eine oder mehr der folgenden:

Erklärung

Frage 13 von 20

Your SMTP email server receives a message addressed to postmaster. The postmaster username has an alias of john on this computer. Assuming that the system is properly configured, who will receive the email message?

Wähle eine der folgenden:

Erklärung

Frage 14 von 20

Which of the following is not a popular SMTP server for Linux?

Wähle eine der folgenden:

Erklärung

Frage 15 von 20

You see the following line in a script: mail -s "Error" -c abort < /tmp/msg root What is the effect of this line, if and when it executes?

Wähle eine der folgenden:

Erklärung

Frage 16 von 20

Your Internet connection has gone down for several hours. What command can you use to check if there is a long list of jobs in the email queue?

Wähle eine der folgenden:

Erklärung

Frage 17 von 20

You examine your /etc/aliases file and find that it contains the following line: root: jody What can you conclude from this?

Wähle eine der folgenden:

Erklärung

Frage 18 von 20

You’ve just installed MySQL and run it by typing mysql. How would you create a database called fish to store data on different varieties of fish?

Wähle eine der folgenden:

Erklärung

Frage 19 von 20

Which of the following are true statements about SQL tables? (Select two.)

Wähle eine oder mehr der folgenden:

Erklärung

Frage 20 von 20

What is the effect of the following SQL command, assuming the various names and data exist? mysql> UPDATE stars SET magnitude=2.25 WHERE starname='Mintaka';

You want to create a shortcut command for the command cd ~/papers/trade. Which of
the following lines, if entered in a bash startup script, will accomplish this goal?

If typed in a bash shell, which of the following commands will create an environment variable called MYVAR with the contents mystuff that will be accessible to any created subshells?
(Choose all that apply.)

What commands might you use (along with appropriate options) to learn the value of a
specific environment variable? (Select two.)

Immediately after creating a shell script called a_script.sh in a text editor, which method
will not work to run the script?

Describe the effect of the following short script, cp1.sh, if it’s called as cp1.sh big.c
big.cc:
#!/bin/bash
cp $2 $1

Which of the following lines identify valid shell scripts on a normally configured system?
(Select two.)

Your SMTP email server receives a message addressed to postmaster. The postmaster
username has an alias of john on this computer. Assuming that the system is properly configured, who will receive the email message?

You see the following line in a script:
mail -s "Error" -c abort < /tmp/msg root
What is the effect of this line, if and when it executes?

Your Internet connection has gone down for several hours. What command can you use to
check if there is a long list of jobs in the email queue?

You examine your /etc/aliases file and find that it contains the following line:
root: jody
What can you conclude from this?

You’ve just installed MySQL and run it by typing mysql. How would you create a database
called fish to store data on different varieties of fish?

What is the effect of the following SQL command, assuming the various names and
data exist?
mysql> UPDATE stars SET magnitude=2.25 WHERE starname='Mintaka';