069-the-bzip2-command.md

The bzip2 command

The bzip2 command lets you compress and decompress the files i.e. it helps in binding the files into a single file which takes less storage space as the original file use to take.

Syntax:

bzip2 [OPTIONS] filenames ...

Note : Each file is replaced by a compressed version of itself, with the name original name of the file followed by extension bz2.

Options and their Functionalities:

Option	Alias	Description
-d	--decompress	to decompress compressed file
-f	--force	to force overwrite an existing output file
-h	--help	to display the help message and exit
-k	--keep	to enable file compression, doesn't deletes the original input file
-L	--license	to display the license terms and conditions
-q	--quiet	to suppress non-essential warning messages
-t	--test	to check integrity of the specified .bz2 file, but don't want to decompress them
-v	--erbose	to display details for each compression operation
-V	--version	to display the software version
-z	--compress	to enable file compression, but deletes the original input file

By default, when bzip2 compresses a file, it deletes the original (or input) file. However, if you don't want that to happen, use the -k command line option.

Examples:

1. To force compression:

bzip2 -z input.txt

Note: This option deletes the original file also

2. To force compression and also retain original input file:

bzip2 -k input.txt

3. To force decompression:

bzip2 -d input.txt.bz2

4. To test integrity of compressed file:

bzip2 -t input.txt.bz2

5. To show the compression ratio for each file processed:

bzip2 -v input.txt