bzip2 and bunzip2 are file compression and decompression utilities. The bzip2 and bunzip2 utilities are newer than gzip and gunzip and are not as common yet, but they are rapidly gaining popularity. The bzip2 utility is capable of greater compression ratios than gzip. Therefore, a bzip2 file can be 10-20% smaller than a gzip version of the same file. Usually, files that have been compressed by bzip2 will have a .bz2 extension.
Installing bzip2 in debian
#apt-get install bzip2
Uncompressing a bzip2 File Using bunzip2
To uncompress a bzip2 file, execute the following command:
#bunzip2 filename.txt.bz2 (where filename.txt.bz2 is the name of the file you wish to uncompress)
The result of this operation is a file called filename.txt. By default, bunzip2 will delete the filename.txt.bz2 file.
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