Linux For Dummies. Richard Blum

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СКАЧАТЬ native instruction set. To make changes to this software, a programmer needs access to a program’s source code. Most proprietary software comes only as a precompiled product; the software developer keeps the source code for those programs under lock and key.

      After determining that his operating system would be built around the conceptual framework of UNIX, Stallman wanted the project name to distinguish his system from UNIX. So, he chose the recursive acronym GNU (pronounced ga-new), which means GNUs not Unix.

      To finance the GNU project, Stallman organized the Free Software Foundation (FSF), which sold open source software to help feed the programmers who worked on its continuing development. (Remember, we’re talking free as in freedom, not free lunch.) Although this organization and goal of creating a complete operating system was necessary and important, a much more important piece of the puzzle had to be put into place to protect this new software from big-business pirates — a concern still all too relevant today as a former Linux company tries to hijack ownership of decades of volunteer work from thousands of people around the world.

      The GNU General Public License (GPL) is a unique and creative software license that uses copyright law to protect the freedom of the software user, which is usually the opposite of how a copyright works. Generally, a copyright is an enforceable designation of ownership and restriction from duplication by anyone but the copyright holder. When software is licensed under the GPL, recipients are bound by copyright law to respect the freedom of anyone else to use the software in any way they choose. Software licensed with the GPL is also known as copyleft software (the reverse of right, get it?). Another way to remember the GPL is through its ultimate result: Guaranteed Public for Life.

While Stallman's work set the stage for Linux's rapid climb to popularity, the operating system he and his crew were working on took longer than expected. If you're interested in the completed version, go to www.gnu.org/software/hurd/hurd.html.

      Who’s in charge of Linux, anyway?

      As an open source project evolves, various people emerge as leaders. This leader is often known as the project’s benevolent dictator. A person who becomes benevolent dictator has probably spent more time than anyone else on a particular problem and often has some unique insight. Normally, the words democratic and dictator are never paired in the same sentence, but the open source model is a very democratic process that endorses the reign of a benevolent dictator.

      Linus Torvalds is still considered the benevolent dictator of the Linux kernel (the operating system’s core). He ultimately determines what features are added to the kernel and what features aren’t. The community trusts his vision and discretion. In the event that he loses interest in the project, or the community decides that he has gone senile, a new leader will emerge from amongst the very competent people working with him.

      Einstein was a volunteer

      Someone who is a volunteer or donates time to a project isn’t necessarily providing a second-rate effort (or only working on weekends and holidays). In fact, any human resources expert will tell you that people who choose to do a job of their own free will produce the highest quality products.

      The volunteers who contribute to open source projects are often leaders in their fields who depend on community collaboration to get useful work done. The open source concept is no stranger to the scientific community. The impartial peer-review process that open source projects foster is critical in validating some new feature or capability as being technically correct.

      

Those who paint the open source community as copyright violators and thieves often misunderstand — or outright ignore — these vital issues. Open source programmers are very proud of their work and are also very concerned about their own copyrights, not wanting their work to be stolen by others — hence licenses such as the GPL. This concern creates an atmosphere with the greatest respect for copyright. Bandits who claim that they’re “just being open source” when they steal other people’s hard work are grossly misusing the term to soothe their own consciences.

Many have also pointed out that if copyright is violated in open source, it’s easy to tell. Watch the news and notice how often large software corporations are convicted of stealing other people’s code and incorporating it into their own work. If the final product is open source, it’s easy for anyone to look and make sure nothing stolen is in it. As you might imagine, tracking down such copyright violations is much more difficult in a closed source scheme.

Packaging Linux: The Distribution

      A complete Linux system package is called a distribution. A Linux distribution contains the Linux kernel, the GNU project's tools, and any number of open source software projects to provide various functionality for the system.

      Lots of different Linux distributions are available to meet just about any computing requirement you could have. Most distributions are customized for a specific user group, such as business users, multimedia enthusiasts, software developers, or normal home users.

      Each customized distribution includes the software packages required to support specialized functions, such as audio and video editing software for multimedia enthusiasts, or compilers and integrated development environments (IDEs) for software developers.

      The different Linux distributions are often divided into three categories:

       Full core Linux distributions

       Specialized distributions

       Live test distributions

      The following sections describe these different types of Linux distributions, and shows some examples of Linux distributions in each category.

      Core Linux distributions

      A core Linux distribution contains the Linux and GNU operating system, one or more graphical desktop environments, and just about every Linux application that is available, ready to install and run. The core Linux distribution provides one-stop shopping for a complete Linux installation, no matter what your requirements are!

Table 1-1 shows some of the more popular core Linux distributions out there.

TABLE 1-1 Core Linux Distributions

Distribution	Description
Slackware	One of the original Linux distribution sets, popular with Linux geeks
Red Hat	A commercial business distribution used mainly for servers
CentOS	The open source version of Red Hat designed for testing
Fedora	Another open source version of Red Hat, but designed for home use
Gentoo	A distribution designed for advanced Linux users, containing СКАЧАТЬ В начало < 8 9 10 11 12 13 14 15 16 17 > В конец