372Part IIIChoosing and Installing a (Business web site) Linux DistributionGentoo s focus
372Part IIIChoosing and Installing a Linux DistributionGentoo s focus on tools for managing and building source code has helped makeGentoo extraordinarily portable. Besides the common x86 (PC) version of Gentoo, there are Gentoo ports for AMD64, PowerPC, UltraSparc, ALpha, and MIPS proces- sors. There are also optimized Linux kernels available with Gentoo for different specific processors within each architecture. Some of the ports are still a work inprogress, so at the moment you will probably get the best experience using an x86platform to run Gentoo. To explore Gentoo, it s more appropriate to start with the tools for getting what youwant than it is to talk about what you end up with. If you build Gentoo turned toyour hardware and include just the software that you need, your system isn t goingto look like any other Gentoo system. Managing Software with PortageAt the heart of Gentoo is the Portage software management system. Based on theFreeBSD Ports system, Portage enables you to find, download, configure, build, andinstall the exact software you choose. Using the portage system can give you some excellent insights into how Linux iscreated. As Daniel Robbins says, . . .we are documenting how to build a Linux system at the same time we are moving Gentoo Linux development forward. Those developing software are encouraged not only to contribute their software tothe Gentoo project but also to contribute the scripts they use to build that software. Portage tools and build scripts open up Linux technology beginning at the source- code level. Key components of the Portage package management system include the emergecommand and the package build scripts (contained in the /usr/portagedirec- tory). You can use these tools to build the entire Gentoo distribution from scratchor rely on some prebuilt binaries to save some compile time. In most cases, youwon t have to modify any configuration files to get a solid Gentoo installation. Following are some examples of the emergecommand that you can use with Gentoo. To use some of the examples, you need to either have a connection to the Internetor have downloaded all package updates to your local computer. When the emergecommand is run to install software or to get updated software packages, it looks ona Gentoo mirror site if it can t find the packages it needs locally. The first examplelets you search (-s) the /usr/portagedirectory tree for packages that interestyou (substitute the package name you want for package): # emerge -s packageTo build and install a package you choose, simply type emergewith the packagename: # emerge package20_