brayhan gutierrez cespedes
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brayhan gutierrez cespedes
Created by brayhan gutierrez cespedes over 6 years ago
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Question 1 of 20

1

Compression on a file works by:

Select one of the following:

  • Removing redundant information

  • Eliminating gaps within the file

  • Storing most of the data on removable media and just leaving a pointer

  • Consolidating multiple files into one

  • Removing the high order bit from each byte

Explanation

Question 2 of 20

1

In general, for which of the following would you want to use lossless compression?

Select one of the following:

  • A log file

  • A movie

  • A JPEG image

  • An mp3 audio file

  • An encrypted email

Explanation

Question 3 of 20

1

Lossy compression:

Select one or more of the following:

  • Decompresses to an identical version as the original

  • Is often used with documents

  • Is often used with images

  • Usually results better compression than lossless

  • Sacrifices some quality

Explanation

Question 4 of 20

1

You type gzip myfile.tar. What happens?

Select one or more of the following:

  • myfile.tar is removed

  • myfile.tar.gz holds a compressed version of myfile.tar

  • An error; you forgot to specify the file with –f

  • myfile.tar is unarchived into the current directory

  • An error; you forgot to pass the name of the output file

Explanation

Question 5 of 20

1

How would you obtain output similar to the following?
compressed​​ ​​​uncompressed ratio uncompressed_name
278168 1016950 72.6% tags

Select one of the following:

  • gunzip –t tags

  • file tags

  • gzip –l tags

Explanation

Question 6 of 20

1

Which command would you use to archive the Documents directory and compress it with bzip2 compression?

Select one of the following:

  • tar –czf documents.tbz Documents

  • tar –cjf Documents

  • tar –fzc Documents documents.tbz

  • tar –cjf documents.tbz Documents

  • tar –cf Documents documents.tbz

Explanation

Question 7 of 20

1

Which flag would you pass to tar in order to have it make a new archive?

Select one of the following:

  • –t

  • -c

  • –j

  • -x

  • –n

Explanation

Question 8 of 20

1

Which command will show what is inside the compressed tarball with a name of foo.tar.gz?

Select one of the following:

  • tar –tjf foo.tar.gz

  • tar –tzf foo.tar.gz

  • tar –lf foo.tar.gz

  • tar –xf foo.tar.gz

  • tar –tf foo.tar.gz

Explanation

Question 9 of 20

1

In the command tar –cvjf foo.tbz a b c, what are a, b, and c?

Select one of the following:

  • File names to be added to the archive

  • Matching operators; anything starting with a, b, or c will be added

  • a is the directory that will be prepended to files; b and c are files inside it

  • Extra flags passed to tar

  • Nothing; -cvjf only expects one parameter

Explanation

Question 10 of 20

1

Given the command tar –cvjf homedirs.tbz /home, which of the following are true?

Select one or more of the following:

  • The /home directory will be restored with the contents of homedirs.tbz

  • Only files starting with /home will be extracted from the archive

  • The command will print out each filename as it is processed

  • Files that are present in the archive might overwrite files in /home

  • The output file will be compressed

Explanation

Question 11 of 20

1

You archived your users’ directories into a file called backup.tar.gz. You then view the archive and see the filenames follow this convention:
home/username/somefile

Select one of the following:

  • How will you extract just the files for the user called fred?

  • tar –tzf /home/fred < backup.tar.gz

  • tar –tjf backup.tar.gz /home/fred

  • tar –xjf backup.tar.gz home/fred/

  • tar –xzf backup.tar.gz home/fred/

  • tar –xzf backup.tar.gz fred

Explanation

Question 12 of 20

1

Which of the following commands will create a zipfile with the contents of your Documents directory?

Select one of the following:

  • zip –cf mydocs.zip Documents

  • zip –c mydocs.zip Documents

  • zip -r mydocs.zip Documents

  • zip mydocs.zip Documents

  • zip –f mydocs.zip Documents

Explanation

Question 13 of 20

1

Given a file called documents.zip, how can you see what’s in it without extracting the files?

Select one of the following:

  • showzip documents.zip

  • zip –lf documents.zip

  • zip –l documents.zip

  • unzip –list documents.zip

  • unzip –l documents.zip

Explanation

Question 14 of 20

1

Given a file called documents.zip, how can you extract just the files under ProjectX?

Select one of the following:

  • zip –x documents.zip ProjectX

  • unzip documents.zip | grep ProjectX

  • unzip –t documents.zip ProjectX

  • unzip documents.zip ProjectX

  • unzip documents.zip ProjectX/*

Explanation

Question 15 of 20

1

You try to compress a file that is already compressed. Which of the following statements is true?

Select one of the following:

  • The file will not be compressed any further than it already was

  • The compression algorithm needs to be set to the “currently compressed” mode for it to be compressed further

  • The file will actually be uncompressed

  • The file changed while you were compressing it

  • The file will be deleted

Explanation

Question 16 of 20

1

Which of the following commands can be used to compress a file?

Select one or more of the following:

  • bunzip2

  • bzip2

  • gzip

  • zip

  • cat

Explanation

Question 17 of 20

1

The three main modes of tar are:

Select one or more of the following:

  • Copy

  • List

  • Compress

  • Extract

  • Create

Explanation

Question 18 of 20

1

In the command tar –czf foo.tar.gz bar, what is the purpose of the f flag?

Select one of the following:

  • Tells tar to read from the file that follows the flag

  • Tells tar to print the name of each file as it is processed

  • Tells tar to copy only files, and not directories

  • Specifies extra compression is to be used

  • Tells tar to write to the file that follows the flag

Explanation

Question 19 of 20

1

Which two commands do the same thing?

Select one or more of the following:

  • tar –czf foo.tar.gz foo

  • tar –c foo | gzip > foo.tar.gz

  • tar –xzf foo.tar.gz

  • tar –x foo | gzip

  • tar –tzf foo.tar.gz

Explanation

Question 20 of 20

1

Select from the dropdown list to complete the text.

The ( updatedb, search, locate, find ) command is normally executed daily to update the database of all files that are on the system.

Explanation