linux chapter 9

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

-c

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

A log file

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

File names to be added to the archive

The three main modes of tar are: (choose three)

List Create Extract

Compression of a file works by

Removing redundant information

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

Tells tar to write to the file that follows the flag

Given the command tar -cvjf homedirs.tbz /home, which of the following are true? (choose two)

The command will print out each filename as it is processed The output file will be compressed

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

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

Lossy compression: (choose three)

Usually results better compression than lossless Is often used with images Sacrifices some quality

How would you obtain output similar to the following? compressed uncompressed ratio U-N 278168 1016950 72.6% tag

gzip -l tags

You type gzip myfile.tar. What happens? (choose two)

myfile.tar.gz holds a compressed version of myfile.tar myfile.tar is removed

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

tar -cjf documents.tbz Documents

Which two commands do the same thing? (choose two)

tar -czf foo.tar.gz foo tar -c foo | gzip > foo.tar.gz

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

tar -tzf foo.tar.gz

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

tar -xzf backup.tar.gz home/fred/

By default, the zip command replaces uncompressed files with compressed files. True or False?

true

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

unzip -l documents.zip

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

unzip documents.zip ProjectX/*

Which two programs use the Lempel-Ziv-Markov chain algorithm? (choose two)

xz gzip

Which of the following commands can be used to compress a file? (choose three)

zip bzip2 gzip