Php5 Hosting, Mysql, Java, Jsp, Servlet, Tomcat, Ssh, Http Web Server Blog

16 Part I . Linux First Steps Although much of the thrust of corporate Linux efforts is on corporate, enterprise computing, huge improvements are continuing in the desktop arena as well. The KDE and GNOME desktop environments continuously improve the Linux experience for casual users. Major efforts are underway to offer critical pieces of desktop components that are still not available in open source versions, including multimedia software and office productivity applications. Linus continues to maintain and improve the Linux kernel. To get more detailed histories of Linux, I recommend visiting the LWN.net site. LWN.net has kept a detailed Linux timeline from 1998 to the present day. For example, the 2003 timeline is available at http://lwn.net/Articles/ Timeline2003. What s So Great About Linux? Leveraging work done on UNIX and GNU projects helped to get Linux up and running quickly. The culture of sharing in the open source community and adoption of a wide array of tools for communicating on the Internet have helped Linux to move quickly through infancy and adolescence to become a mature operating system. The simple commitment to share code is probably the single most powerful contributor to the growth of the open source software movement in general, and Linux in particular. That commitment has also encouraged involvement from the kind of people who are willing to contribute back to that community in all kinds of ways. The following sections characterize Linux and the communities that support it. OSI Open Source Definition For software developers, Linux provides a platform that lets them change the operating system as they like and get a wide range of help creating the applications they need. One of the watchdogs of the open source movement is the Open Source Initiative (www.opensource.org). This is how the OSI Web site describes open source software: The basic idea behind open source is very simple: When programmers can read, redistribute, and modify the source code for a piece of software, the software evolves. People improve it, people adapt it, people fix bugs. And this can happen at a speed that, if one is used to the slow pace of conventional software development, seems astonishing. We in the open source community have learned that this rapid evolutionary process produces better software than the traditional closed model, in which only a very few programmers can see the source and everybody else must blindly use an opaque block of bits. Note
Note: In case you are looking for affordable webhost to host and run your servlet application check Vision make web site services

Chapter 1 . Starting with Linux 15 Today, BSD versions are available from three projects: FreeBSD, NetBSD, and OpenBSD. People generally characterize FreeBSD as the easiest to use, NetBSD as available on the most computer hardware platforms, and OpenBSD as fanatically secure. Many security-minded individuals still prefer BSD over Linux. Linus Builds the Missing Piece In 1991, Linus Torvalds, a student at the University of Helsinki, Finland, started work on a UNIX-like kernel because he wanted to be able to use the same kind of operating system on his home PC that he used at school. At the time, Linus was using Minix, but he wanted to go beyond what the Minix standards permitted. As noted earlier, Linus announced the first public version of the Linux kernel to the comp.os.minix newsgroup on August 25, 1991. Although Linus guesses that the first version didn t actually come out until mid-September of that year (see the Linux International Web site s Linux History page: www.li.org/linuxhistory.php). Although Torvalds stated that Linux was written for the 386 processor and probably wasn t portable, others persisted in encouraging (and contributing to) a more portable approach in the early versions of Linux. By October 5, Linux 0.02 was released with much of the original assembly code rewritten in the C programming language, which made it possible to start porting it to other machines. The Linux kernel was the last and the most important piece of code that was needed to complete a whole UNIX-like operating system under the GPL. So, when people started putting together distributions, the name Linux and not GNU is what stuck. Some distributions such as Debian, however, refer to themselves as GNU/Linux distributions. Within the next few years, commercial and noncommercial Linux distributions began to emerge. MCC Interim Linux (ftp.mcc.ac.uk/pub/linux/distributions/ MCC) was released in the U.K. in February 1992. Slackware Linux (described in Chapter 14), which was first released in April 1993, is one of the oldest surviving Linux distributions. Today, Linux can be described as an open source UNIX-like operating system that reflects a combination of SVID, POSIX, and BSD compliance. Linux continues to aim toward compliance with POSIX as well as with standards set by the new owner of the UNIX trademark, The Open Group (www.unix-systems.org). The nonprofit Open Source Development Labs (www.osdl.org), which employs Linus Torvalds, manages the direction today of Linux development efforts. Its sponsors list is like a who s who of commercial Linux vendors, including IBM, Red Hat, SUSE (Novell), VA Software, HP, Dell, Computer Associates, Intel, Cisco Systems, and others. OSDL s primary charter is to accelerate the growth of Linux in telecommunications and data centers. Note
Note: If you are looking for best quality webspace to host and run your tomcat application check Vision virtual web hosting services

14 Part I . Linux First Steps To clearly define how open source software should be handled, the GNU software project created the GNU Public License. Although there are many other software licenses covering slightly different approaches to protecting free software, the GPL is perhaps the most well known and it s the one that covers the Linux kernel itself. Basic features of the GNU Public License include: . Author rights The original author retains the rights to his or her software. . Free distribution People can use the GNU software in their own software, changing and redistributing it as they please. They do, however, have to include the source code with their distribution (or make it easily available). . Copyright maintained Even if you were to repackage and resell the software, the original GNU agreement must be maintained with the software, which means all future recipients of the software have the opportunity to change the source code, just as you did. There is no warranty on GNU software. If something goes wrong, the original developer of the software has no obligation to fix the problem. However, many organizations, big and small, offer paid support packages for the software when it is included in their Linux or other open source software distribution. (See the OSI Open Source Definition section later in this chapter for a more detailed definition of open source software.) Despite its success producing thousands of UNIX utilities, the GNU project itself failed to produce one critical piece of code: the kernel. Its attempts to build an open source kernel with the GNU Hurd project (www.gnu.org/software/hurd) were unsuccessful. BSD Loses Some Steam The one software project that had a chance of beating out Linux to be the premier open source software project was the venerable old BSD project. By the late 1980s, BSD developers at UC Berkeley realized that they had already rewritten most of the UNIX source code they had received a decade earlier. In 1989, UCB distributed its own UNIX-like code as Net/1 and later (in 1991) as Net/2. Just as UC Berkeley was preparing a complete, UNIX-like operating system that was free from all AT&T code, AT&T hit them with a lawsuit in 1992. The suit claimed that the software was written using trade secrets taken from AT&T s UNIX system. The lawsuit was dropped when Novell bought UNIX System Laboratories from AT&T in 1994. But, during that critical time period, there was enough fear and doubt about the legality of the BSD code that the momentum BSD had gained to that point in the fledgling open source community was lost. Many people started looking for another open source alternative. The time was ripe for a college student from Finland who was working on his own kernel.
Note: If you are looking for cheap and reliable webhost to host and run your mysql application check Vision professional web hosting services

Chapter 1 . Starting with Linux 13 When USL eventually started taking on marketing experts and creating a desktop UNIX product for end users, Microsoft Windows already had a firm grasp on the desktop market. Also, because the direction of UNIX had always been toward source code licensing destined for large computing systems, USL had pricing difficulties for its products. For example, on software it was including with UNIX, USL found itself having to pay out per-computer licensing fees that were based on $100,000 mainframes instead of $2,000 PCs. Add to that the fact that no application programs were available with UNIXWare, and you can see why the endeavor failed. Successful marketing of UNIX systems at the time, however, was happening with other computer companies. SCO had found a niche market, primarily selling PC versions of UNIX running dumb terminals in small offices. Sun Microsystems was selling lots of UNIX workstations (originally based on BSD but which was merged with UNIX in SVR4) for programmers and high-end technology applications (such as stock trading). Other commercial UNIXs were also emerging by the 1980s as well. This new ownership assertion of UNIX was beginning to take its toll on the spirit of open contributions. Lawsuits were being raised to protect UNIX source code and trademarks. In 1984, this new, restrictive UNIX gave rise to an organization that eventually led a path to Linux: the Free Software Foundation. To a GNU Free-Flowing (Not) UNIX In 1984, Richard M. Stallman started the GNU project (www.gnu.org), recursively named by the phrase GNU is Not UNIX. As a project of the Free Software Foundation (FSF), GNU was intended to become a recoding of the entire UNIX operating system that could be freely distributed. While rewriting millions of lines of code might seem daunting to one or two people, spreading the effort across dozens, or even hundreds, of programmers made the project possible. It turned out that not only could the same results be gained by all new code, but that in some cases that code was better than the original UNIX versions. Because everyone could see the code being produced for the project, poorly written code could be corrected quickly or replaced over time. If you are familiar with UNIX, try searching the more than 3,400 GNU software packages for your favorite UNIX commands from the Free Software Directory (http:// directory.fsf.org/GNU). Chances are you will find it there, along with many, many other software projects available as add-ons. Over time, the term free software has been mostly replaced by the term open source software. This helps bring home the fact that, while you are free to use the software as you like, you have some responsibility to make the improvements you make to the code available to others. In that way, everyone in the community can benefit from your work as you have benefited from others .
Note: In case you are looking for affordable webhost to host and run your servlet application check Vision ecommerce web hosting services

12 Part I . Linux First Steps UNIX Laboratory and Commercialization The UNIX Laboratory was considered a jewel that couldn t quite find a home or a way to make a profit. As it moved between Bell Laboratories and other areas of AT&T, its name changed several times. It is probably best remembered by its last name, which it had as it began its spin off from AT&T: UNIX System Laboratories (USL). The UNIX source code that came out of USL, the legacy of which is now owned by Santa Cruz Operation (SCO), is being used as the basis for lawsuits by SCO against major Linux vendors (such as IBM and Red Hat Inc.). Because of that, I think the efforts from USL that have contributed to the success of Linux are sometimes disrespected. You have to remember that, during the 1980s, many computer companies were afraid that a newly divested AT&T would pose more of a threat to controlling the computer industry than would an upstart company in Redmond, Washington. To calm the fears of IBM, Intel, DEC, and other computer companies, the UNIX Lab made the following commitments to ensure a level playing field: . Source code only Instead of producing its own boxed set of UNIX, AT&T continued to only sell source code and to make it available equally to all licensees. Each company would then port UNIX to its own equipment. It wasn t until about 1992, when the lab was spun off as a joint venture with Novell (called Univel) and then eventually sold to Novell, that a commercial boxed set of UNIX (called UnixWare) was produced directly from that source code. . Published interfaces To create an environment of fairness and community to its OEMs (original equipment manufacturers), AT&T began standardizing what different ports of UNIX had to be able to do to still be called UNIX. To that end, compliance with POSIX standards and the AT&T UNIX System V Interface Definition (SVID) were specifications UNIX vendors could use to create compliant UNIX systems. Those same documents also served as road maps for the creation of Linux. In an early e-mail newsgroup post from Linus Torvalds, Linux makes a request for a copy, preferably online, of the POSIX standard. I think that nobody from AT&T expected someone to actually be able to write their own clone of UNIX from those interfaces without using any of its UNIX source code. . Technical approach Again, until the very end of USL, most decisions on the direction of UNIX were made based on technical considerations. Management was promoted up through the technical ranks, and there was never any talk that I heard of writing software to break other companies software or otherwise restrict the success of USL s partners. Note
Note: In case you are looking for affordable and reliable webhost to host and run your business application check Vision ftp web hosting services

Chapter 1 . Starting with Linux 11 If you are a Linux enthusiast and are interested in what features from the early days of Linux have survived, an interesting read is Dennis Ritchie s reprint of the first UNIX programmer s manual (dated November 3, 1971). You can find it at Dennis Ritchie s Web site: http://cm.bell-labs.com/cm/cs/who/dmr/1stEdman.html. The form of this documentation is UNIX man pages which is still the primary format for documenting UNIX and Linux operating system commands and programming tools today. What s clear as you read through the early documentation and accounts of the UNIX system is that the development was a free-flowing process, lacked ego, and was dedicated to making UNIX excellent. This process led to a sharing of code (both inside and outside of Bell Labs) that allowed rapid development of a highquality UNIX operating system. It also led to an operating system that AT&T would find difficult to reel back in later. To a Commercialized UNIX Before AT&T divestiture in 1984, when it was split up into AT&T and seven baby Bell companies, AT&T was forbidden to sell computer systems. Companies you now know by names such as Verizon, Qwest, SBC Communications, and Lucent Technologies were all part of AT&T. As a result of AT&T s monopoly of the telephone system, the U.S. government was concerned that an unrestricted AT&T might dominate the fledgling computer industry. Because AT&T was restricted from selling computers directly to customers before its divestiture, UNIX source code was licensed to universities for a nominal fee. There was no UNIX operating system for sale from AT&T that you didn t have to compile yourself. BSD Arrives In 1975, UNIX V6 became the first version of UNIX available for widespread use outside of Bell Laboratories. From this early UNIX source code, the first major variant of UNIX was created at University of California at Berkeley. It was named the Berkeley Software Distribution (BSD). For most of the next decade, the BSD and Bell Labs versions of UNIX headed off in separate directions. BSD continued forward in the free-flowing, share-the-code manner that was the hallmark of the early Bell Labs UNIX, while AT&T started steering UNIX toward commercialization. With the formation of a separate UNIX Laboratory, which moved out of Murray Hill and down the road to Summit, New Jersey, AT&T began its attempts to commercialize UNIX. By 1984, divestiture was behind AT&T, and it was ready to really start selling UNIX.
Note: If you are looking for best quality webspace to host and run your tomcat application check Vision virtual web hosting services

10 Part I . Linux First Steps The simplicity and power of the UNIX design began breaking down barriers that impeded software developers. The foundation of UNIX was set with several key elements: . The UNIX file system After creating the structure that allowed levels of subdirectories (which, for today s desktop users, looks like folders inside of folders), UNIX could be used to organize the files and directories in intuitive ways. Furthermore, complex methods of accessing disks, tapes, and other devices were greatly simplified by representing those devices as individual device files that you could also access as items in a directory. . Input/output redirection Early UNIX systems also included the concept of input redirection and pipes. From a command line, UNIX users could direct the output of a command to a file using a right arrow key (>). Later, the concepts of pipes was added (|) where the output of one command could be directed to the input of another command. For example, the command line $ cat file1 file2 | sort | pr | lpr concatenates (cat) file1 and file2, sorts (sort) the lines in those files alphabetically, paginates the sorted text for printing (pr), and directs the output to the computer s default printer (lpr). This method of directing input and output enabled developers to create their own specialized utilities that could be joined together with existing utilities. This modularity made it possible for lots of code to be developed by lots of different people. . Portability Much of the early work in simplifying the experience of using UNIX led to its also becoming extraordinarily portable to run on different computers. By having device drivers (represented by files in the file system tree), UNIX could present an interface to applications in such a way that the programs didn t have to know about the details of the underlying hardware. To later port UNIX to another system, developers only had to change the drivers. The applications program didn t have to change for different hardware! To make the concept of portability a reality, however, a high-level programming language was needed to implement the software needed. To that end, Brian Kernighan and Dennis Ritchie created the C programming language. In 1973, UNIX was rewritten in C. Today, C is still the primary language used to create the UNIX (and Linux) operating system kernels. As Ritchie went on to say in his 1980 lecture: Today, the only important UNIX program still written in assembler is the assembler itself; virtually all the utility programs are in C, and so are most of the applications programs, although there are sites with many in Fortran, Pascal, and Algol 68 as well. It seems certain that much of the success of UNIX follows from the readability, modifiability, and portability of its software that in turn follows from its expression in high-level languages.
Note: If you are looking for high quality webhost to host and run your jsp application check Vision jsp web hosting services

Chapter 1 . Starting with Linux 9 my OS resembles it somewhat (same physical layout of the file-system (due to practical reasons) among other things)… Any suggestions are welcome, but I won t promise I ll implement them Linus (torvalds@kruuna.helsinki.fi) PS. Yes it s free of any minix code, and it has a multi-threaded fs. It is NOT protable[sic] (uses 386 task switching etc), and it probably never will support anything other than AT-harddisks, as that s all I have . Reprinted from Linux International Web site (www.li.org/linuxhistory.php) Minix was a free UNIX-like operating system that ran on PCs in the early 1990s. Like Minix, Linux was also a clone of the UNIX operating system. To truly appreciate how a free operating system could have been modeled after a proprietary system from AT&T Bell Laboratories, it helps to understand the culture in which UNIX was created and the chain of events that made the essence of UNIX possible to reproduce freely. From a Free-Flowing UNIX Culture at Bell Labs From the very beginning, the UNIX operating system was created and nurtured in a communal environment. Its creation was not driven by market needs but by a desire to overcome impediments to producing programs. AT&T, which owned the UNIX trademark originally, eventually made UNIX into a commercial product, but by that time, many of the concepts (and even much of the early code) that made UNIX special had fallen into the public domain. If you are under 30 years old, you may not remember a time when AT&T was the phone company. Up until the early 1980s, AT&T didn t have to think much about competition because if you wanted a phone in the United States, you had to go to AT&T. It had the luxury of funding pure research projects. The Mecca for such projects was the Bell Laboratories site in Murray Hill, New Jersey. After the failure of a project called Multics around 1969, Bell Labs employees Ken Thompson and Dennis Ritchie set off on their own to create an operating system that would offer an improved environment for developing software. Up to that time, most programs were written on punch cards that had to be fed in batches to mainframe computers. In a 1980 lecture on The Evolution of the UNIX Time-sharing System, Dennis Ritchie summed up the spirit that started UNIX: What we wanted to preserve was not just a good environment in which to do programming, but a system around which a fellowship could form. We knew from experience that the essence of communal computing as supplied by remote-access, time-shared machines is not just to type programs into a terminal instead of a keypunch, but to encourage close communication.
Note: If you are looking for high quality webhost to host and run your jsp application check Vision christian web host services

8 Part I . Linux First Steps . Portable software You can usually change to another Linux, UNIX, or BSD system and still use the exact same software! Most open source software projects were created to run on any UNIX-like system, and many also run on Windows systems, if you need them to. If it won t run where you want it to, chances are that you, or someone you hire, can port it to the computer you want. . Downloadable applications If the applications you want are not delivered with your version of Linux, you can often download and install them with a single command, using tools such as apt and yum. . No settings hidden in code or registries Once you learn your way around Linux, you ll find that (given the right permissions on your computer) most configuration is done in plain-text files that are easy to find and change. . Mature desktop The X Window System (providing the framework for your Linux desktop) has been around longer than Microsoft Windows. The KDE and GNOME desktop environments provide graphical interfaces (windows, menus, icons, and so forth) that rival those on Microsoft systems. Ease-of-use problems with Linux systems are rapidly evaporating. . Freedom Linux, in its most basic form, has no corporate agenda or bottom line to meet. You are free to choose the Linux distribution that suits you, look at the code that runs the system, add and remove any software you like, and make your computer do what you want it to do. Some aspects of Linux make it hard for some new users to get started. One is that Linux is typically set up to be secure by default, so you need to adjust to using an administrative login (root) to make most changes that affect the whole computer system. Although this can be a bit inconvenient, trust me, it makes your computer safer than just letting anyone do anything. For the same reason, many services are off by default, so you need to turn them on and do at least minimal configuration to get them going. Linux can be more difficult than Windows because it is just different, but because you re reading this book, I assume you want to learn about those differences. Exploring Linux History Some histories of Linux begin with this message posted by Linus Torvalds to the comp.os.minix newsgroup on August 25, 1991: Hello everybody out there using minix - I m doing a (free) operating system (just a hobby, won t be big and professional like gnu) for 386(486) AT clones. This has been brewing since april, and is starting to get ready. I d like any feedback on things people like/dislike in minix, as
Note: If you are looking for cheap webhost to host and run your apache application check Vision jboss web hosting services

Chapter 1 . Starting with Linux 7 . Applications Although no Linux distribution includes all of them, there are literally thousands of games, office productivity tools, Web browsers, chat windows, multimedia players, and other applications available for Linux. . Programming tools Including programming utilities for creating applications and libraries for implementing specialty interfaces. . Server features Enabling you to offer services from your Linux computer to another computer on the network. In other words, while Linux includes Web browsers to view Web pages, it can also be the computer that serves up Web pages to others. Popular server features include Web, mail, database, printer, file, DNS, and DHCP servers. Once Linus Torvalds and friends had a working Linux kernel, pulling together a complete open source operating system was possible. The reason this could be done was because so much of the available free software was: . Covered by the GNU Public License (GPL) or similar license. That allowed the entire operating system to be freely distributed, provided that some guidelines were followed relating to how the source code for that software was made available going forward. . Based on UNIX-like systems. Clones of virtually all the other user-level components of a UNIX system had been created. Those and other utilities and applications were built to run on UNIX or other UNIX-like systems. Linux has become the culmination of the open source software movement. But the traditions of sharing code and building communities that made Linux possible started years before Linux was born. You could argue that it began in a comfortable think tank known as Bell Laboratories. What s So Cool About Linux? If you have not used Linux before, you should expect a few things to be different from other operating systems. Here is a brief list of some features that you might find cool about using Linux: . No rebooting to install Uptime is valued as a matter of pride (remember, Linux and other UNIX systems are most often used as servers, which are expected to stay up 24×7). After the original installation, you can install or remove most software without having to reboot your computer. . Start/stop services without interrupting others You can start and stop individual services (such as Web, file, and e-mail services) without rebooting or even interrupting the work of any other users or features of the computer. In other words, you should not have to reboot your computer every time someone sneezes.
Note: If you are looking for cheap webhost to host and run your apache application check Vision apache web hosting services