010-160 Archiving and Compression 5

Question 1

What happens when you run `gzip` on a file that is already compressed (e.g., a .jpg)?

Accepted Answer

It compresses it anyway, often resulting in a larger file

Answer

gzip compresses any file regardless of type, but already-compressed formats like JPEG gain little and may even grow slightly.

Question 2

Which command extracts only a specific file from a tar archive?

Accepted Answer

tar -xf archive.tar path/to/file.txt

Answer

You can specify one or more filenames after the archive name with tar -xf to extract only those specific files.

Question 3

What is the purpose of `tar --listed-incremental=snapshot.file`?

Accepted Answer

Create an incremental backup using a snapshot file to track changes

Answer

This option enables incremental backups by recording file metadata in the snapshot file and only archiving changed files on subsequent runs.

Question 4

Which command shows compression statistics like compressed size, original size, and ratio for a .gz file?

Accepted Answer

gzip -l file.gz

Answer

The -l (list) option displays compression statistics including compressed size, uncompressed size, and compression ratio.

Question 5

What does `tar -uvf archive.tar newfile.txt` do?

Accepted Answer

Appends newfile.txt only if it is newer than the version in the archive

Answer

The -u (update) flag adds files to the archive only if they are newer than the existing archived version.

(010-160) LPI Linux Essentials Practice Test