bzip2 command in Linux with Examples

bzip2 command in Linux is used to compress and decompress the files i.e. it helps in binding the files into a single file which takes less storage space than the original file used to take. It has a slower decompression time and higher memory use. It uses the Burrows-Wheeler block sorting text compression algorithm and Huffman Coding. Each file is replaced by a compressed version of itself, with the name original name of the file followed by the extension bz2.

Consider this example using bzip2.

Command:

​bzip2 -k file1.txt

Output:

What it does:

• Creates input.txt.bz2 while keeping file1.txt due to -k; without -k, file1.txt would be removed after compression.

Syntax

bzip2 [OPTIONS] filenames ...

Each provided file is compressed individually to file.bz2; to decompress, use bunzip2 or bzip2 -d.

Commonly Used Options in bzip2

1. Compress a File (-z Option)

The -z option forces compression, though it is the default action of the bzip2 command. When you run this command, the original file is replaced by the compressed version.

$ bzip2 -z input.txt

2. Keep the Original File (-k Option)

Normally, bzip2 deletes the original file after compression, but the -k option ensures the original file is preserved alongside the compressed version.

$ bzip2 -k input.txt

3. Decompress a File (-d Option)

The -d option is used for decompressing files that were previously compressed using bzip2.

$ bzip2 -d input.txt.bz2

4. Integrity Check (-t Option)

If you want to check whether a .bz2 file is corrupted without decompressing it, the -t option comes in handy. It checks the integrity of the file and informs you if it's corrupted.

$ bzip2 -t input.txt.bz2

5. Verbose Mode (-v Option)

The -v option enables verbose mode, where the command shows additional information, such as compression ratios and other diagnostics, during the compression process.

$ bzip2 -v input.txt

Other Available Options

The bzip2 command is an essential tool for compressing files in Linux, especially when storage space is a concern. While it offers excellent compression ratios, its higher memory usage and slower decompression times make it better suited for specific use cases, such as long-term storage or data transfers where space efficiency is critical.