To compress a file(s), is to significantly decrease the size of the file(s) by encoding data in the file(s) using less bits, and it is normally a useful practice during backup and transfer of a file(s) over a network. On the other hand, decompressing a file(s) means restoring data in the file(s) to its original state.
Bzip2 is a well-known compression tool and it’s available on most if not all the major Linux distributions, you can use the appropriate command for your distribution to install it.
$ sudo apt install bzip2 [On Debian/Ubuntu] $ sudo yum install bzip2 [On CentOS/RHEL] $ sudo dnf install bzip2 [On Fedora 22+]
The conventional syntax of using bzip2 is:
$ bzip2 option(s) filenames
How to Use “bzip2” to Compress Files in Linux
You can compress a file as below, where the flag -z enables file compression:
$ bzip2 filename OR $ bzip2 -z filename
To compress a .tar file, use the command format:
$ bzip2 -z backup.tar
Important: By default, bzip2 deletes the input files during compression or decompression, to keep the input files, use the -k or --keep option.
In addition, the -f or --force flag will force bzip2 to overwrite an existing output file.
------ To keep input file ------ $ bzip2 -zk filename $ bzip2 -zk backup.tar
You can as well set the block size to 100k upto 900k, using -1 or --fast to -9 or –best as shown in the below examples:
$ bzip2 -k1 Etcher-linux-x64.AppImage $ ls -lh Etcher-linux-x64.AppImage.bz2 $ bzip2 -k9 Etcher-linux-x64.AppImage $ bzip2 -kf9 Etcher-linux-x64.AppImage $ ls -lh Etcher-linux-x64.AppImage.bz2
How to Use “bzip2” to Decompress Files in Linux
To decompress a .bz2 file, make use of the -d or --decompress option like so:
$ bzip2 -d filename.bz2
Note: The file must end with a .bz2 extension for the command above to work.
$ bzip2 -vd Etcher-linux-x64.AppImage.bz2 $ bzip2 -vfd Etcher-linux-x64.AppImage.bz2 $ ls -l Etcher-linux-x64.AppImage
To view the bzip2 help page and man page, type the command below:
$ bzip2 -h $ man bzip2