Running Linux, 5th Edition

Archive and Compression Utilities

When installing or upgrading software on Unix systems, the first things you need to be familiar with are the tools used for compressing and archiving files. Dozens of such utilities are available. Some of these (such as tar and compress) date back to the earliest days of Unix; others (such as gzip and the even newer bzip2) are relative newcomers. The main goal of these utilities is to archive files (that is, to pack many files together into a single file for easy transportation or backup) and to compress files (to reduce the amount of disk space required to store a particular file or set of files).

In this section, we're going to discuss the most common file formats and utilities you're likely to run into. For instance, a near-universal convention in the Unix world is to transport files or software as a tar archive, compressed using compress, gzip, or bzip2. In order to create or unpack these files yourself, you'll need to know the tools of the trade. The tools are most often used when installing new software or creating backups—the subject of the following two sections in this chapter. Packages coming from other worlds, such as the Windows or Java world, are often archived and compressed using the zip utility; you can unpack these with the unzip command, which should be available in most Linux installations.^[*]

Using gzip and bzip2

gzip is a fast and efficient compression program distributed by the GNU project. The basic function of gzip is to take ...