Linux kernel: Difference between revisions
imported>Eric M Gearhart (I'm renaming "See Also" to "Related Topics" or "Subtopics" as appropriate. See http://forum.citizendium.org/index.php/topic,513.0.html for details on this) |
mNo edit summary |
||
(16 intermediate revisions by 9 users not shown) | |||
Line 1: | Line 1: | ||
{{subpages}} | |||
{{dambigbox|the [[operating system]] [[kernel]]|Linux}} | |||
{| cellpadding="1" style="float: right; border: 1px solid #aaa; background: #f9f9f9; padding: 5px; font-size: 90%; margin: 0 0 15px 15px; clear: right;" | {| cellpadding="1" style="float: right; border: 1px solid #aaa; background: #f9f9f9; padding: 5px; font-size: 90%; margin: 0 0 15px 15px; clear: right;" | ||
|- | |- | ||
Line 15: | Line 17: | ||
| style="padding: 0.25em;"|'''Source model:''' [[Open source]] | | style="padding: 0.25em;"|'''Source model:''' [[Open source]] | ||
|- | |- | ||
| style="padding: 0.25em;"|'''Latest stable release:''' Kernel 2.6. | | style="padding: 0.25em;"|'''Latest stable release:''' Kernel 2.6.22.1 / Jul 10 2007 | ||
|- | |- | ||
| style="padding: 0.25em;"|'''Supported platforms:''' [[X86 architecture|x86]], [[x86-64]], [[ia64]], [[DEC Alpha]], <br/> [[Motorola 68k]], [[SUN Sparc]], [[ARM]], [[PowerPC]] | | style="padding: 0.25em;"|'''Supported platforms:''' [[X86 architecture|x86]], [[x86-64]], [[ia64]], [[DEC Alpha]], <br/> [[Motorola 68k]], [[SUN Sparc]], [[ARM]], [[PowerPC]] | ||
Line 29: | Line 31: | ||
|} | |} | ||
The '''Linux kernel''' is the "traffic cop" of [[Linux]], the part of the [[operating system]] that controls processes, manages memory, and loads drivers. The first Linux kernel was implemented by [[Linus Torvalds]], a [[Finland|Finnish]] software student. Torvalds started work on Linux to provide a free Unix-like alternative to the [[Minix]] operating system, owned and developed by eminent Professor [[Andrew Tanenbaum]]. Both Linux and Minix share the distinction of running on an Intel [[x86]] chip architecture, which before this time was dominated mainly by Microsoft's DOS and Windows. The advent of Linux made available to the public a free alternative to Windows, which also ran on the exact same low-cost hardware. Linux advocates praise it for being relatively stable and secure and quite low-cost. | |||
The '''Linux kernel''' is the traffic cop of [[Linux]], the part of the [[operating system]] that controls processes, manages memory, and loads drivers. The first Linux kernel was implemented by [[Linus Torvalds]], a [[Finland|Finnish]] software student. Torvalds | |||
Linux | |||
==Licensing== | ==Licensing== | ||
Line 43: | Line 41: | ||
| url=http://groups.google.com/group/comp.os.minix/browse_thread/thread/76536d1fb451ac60/b813d52cbc5a044b?lnk=gst | | url=http://groups.google.com/group/comp.os.minix/browse_thread/thread/76536d1fb451ac60/b813d52cbc5a044b?lnk=gst | ||
| title=Linus' first USENET post concerning Linux | | title=Linus' first USENET post concerning Linux | ||
| date= | | date=Retrieved 07-April-2007 | ||
}}</ref> <ref name="LINUX's History by Linus Torvalds">{{cite web | }}</ref> <ref name="LINUX's History by Linus Torvalds">{{cite web | ||
| url=http://www.cs.cmu.edu/~awb/linux.history.html | | url=http://www.cs.cmu.edu/~awb/linux.history.html | ||
| title=LINUX's History by Linus Torvalds | | title=LINUX's History by Linus Torvalds | ||
| date= | | date=Retrieved 07-April-2007 | ||
}}</ref> by a [[Finland|Finnish]] [[software]] [[engineer]] named [[Linus Torvalds]], and is now maintained largely by the [[open source community|community]]. | }}</ref> by a [[Finland|Finnish]] [[software]] [[engineer]] named [[Linus Torvalds]], and is now maintained largely by the [[open source community|community]]. | ||
On August 25th 1991<ref name= "First USENET Post"/> Torvalds posted publicly on [[USENET]] the first post describing "a (free) operating system (just a hobby, won't be big and professional like gnu) for 386(486) AT clones." | On August 25th 1991<ref name= "First USENET Post"/> Torvalds posted publicly on [[USENET]] the first post describing "a (free) operating system (just a hobby, won't be big and professional like gnu) for 386(486) AT clones." | ||
Torvalds' project soon grew in popularity as a free alternative to [[Minix]]. He now acts more as a 'Benevolent Dictator for Life' and coordinates patches and improvements to the kernel, rather than directly [[hacking]] source code himself. | Torvalds' project soon grew in popularity as a free alternative to [[Minix]]. He now acts more as a '[[Benevolent Dictator for Life]]' and coordinates patches and improvements to the kernel, rather than directly [[hacking]] source code himself. | ||
==Architecture== | ==Architecture== | ||
Much like its predecessor Unix, the Linux kernel is written in the [[C programming language|C programming language]], as well as some architecture-specific assembly to increase performance on specific [[CPU|processors]]. The design of the kernel is [[Monolithic (kernels)|Monolithic]], with the ability to load modules on the fly (modules are usually thought of as drivers in the Windows world). The current release holds more than 40 [[byte|megabytes]] of source code, contributed by more than a thousand [[hackers]]. | |||
The kernel was originally written with only the [[Intel 386]] processor in mind. (Linus stated that he wrote the OS as a lesson in the architecture of the 386). That limitation has since been overcome, and it has since been [[ported (software)|ported]] to many different architectures on many different platforms, even surpassing the traditional Unix that is known to "run on anything," [[NetBSD]]. | The kernel was originally written with only the [[Intel 386]] processor in mind. (Linus stated that he wrote the OS as a lesson in the architecture of the 386). That limitation has since been overcome, and it has since been [[ported (software)|ported]] to many different architectures on many different platforms, even surpassing the traditional Unix that is known to "run on anything," [[NetBSD]]. | ||
Line 70: | Line 68: | ||
== References == | == References == | ||
<references/> | <references/>[[Category:Suggestion Bot Tag]] | ||
[[Category: |
Latest revision as of 11:00, 12 September 2024
Linux |
Tux the penguin, the Linux mascot |
Website: http://www.linux.org |
Developer: The Open Source community |
OS family: Unix-like |
Source model: Open source |
Latest stable release: Kernel 2.6.22.1 / Jul 10 2007 |
Supported platforms: x86, x86-64, ia64, DEC Alpha, Motorola 68k, SUN Sparc, ARM, PowerPC |
Kernel type: Monolithic kernel |
Default user interface: Command line |
License: GNU General Public License |
Working state: Current |
The Linux kernel is the "traffic cop" of Linux, the part of the operating system that controls processes, manages memory, and loads drivers. The first Linux kernel was implemented by Linus Torvalds, a Finnish software student. Torvalds started work on Linux to provide a free Unix-like alternative to the Minix operating system, owned and developed by eminent Professor Andrew Tanenbaum. Both Linux and Minix share the distinction of running on an Intel x86 chip architecture, which before this time was dominated mainly by Microsoft's DOS and Windows. The advent of Linux made available to the public a free alternative to Windows, which also ran on the exact same low-cost hardware. Linux advocates praise it for being relatively stable and secure and quite low-cost.
Licensing
The Linux kernel is a free, Unix-like, open source project licensed under the GNU General Public License. Specifically, version 2.0 of the GPL is applied to the kernel, without the "or any future versions" clause. This was an intentional move by Torvalds, and ties the kernel directly to version 2.0 of the GPL.
History
The Linux kernel was created in April 1991[1] [2] by a Finnish software engineer named Linus Torvalds, and is now maintained largely by the community. On August 25th 1991[1] Torvalds posted publicly on USENET the first post describing "a (free) operating system (just a hobby, won't be big and professional like gnu) for 386(486) AT clones."
Torvalds' project soon grew in popularity as a free alternative to Minix. He now acts more as a 'Benevolent Dictator for Life' and coordinates patches and improvements to the kernel, rather than directly hacking source code himself.
Architecture
Much like its predecessor Unix, the Linux kernel is written in the C programming language, as well as some architecture-specific assembly to increase performance on specific processors. The design of the kernel is Monolithic, with the ability to load modules on the fly (modules are usually thought of as drivers in the Windows world). The current release holds more than 40 megabytes of source code, contributed by more than a thousand hackers.
The kernel was originally written with only the Intel 386 processor in mind. (Linus stated that he wrote the OS as a lesson in the architecture of the 386). That limitation has since been overcome, and it has since been ported to many different architectures on many different platforms, even surpassing the traditional Unix that is known to "run on anything," NetBSD.
Portability and Stability
Initially developed and used primarily by individual enthusiasts on personal computers, Linux has since gained the support of corporations such as IBM, Sun Microsystems, Hewlett-Packard, and Novell, Inc., and has risen to prominence as an operating system for servers; Netcraft reported in September 2006 that seven of the ten most reliable Internet hosting companies run Linux on their web servers. [3]
Linux is nowadays used in devices ranging from supercomputers to mobile phones, and has a foothold in the personal computer and business desktop markets.
Kernel Versioning
The current version of the Linux kernel is 2.6.20.4 as of March 2007. The first number refers to the kernel version. The Linux kernel has been on version 2 since 1996. The second number is called the major version number. It has been major version 6 since December 2003. The third number is the minor revision, and reflects the addition of drivers or features to the kernel. It is changed much more frequently than the first two numbers. The fourth number is sometimes used in the event of bug fixes or security updates of a critical nature, while an odd number denotes a developmental version.
Common Examples of Linux Distributions
The Linux kernel is most often found in a collection of software known as a Linux distribution, examples being Ubuntu, Fedora Core, and SUSE. Distributions provide an easier method of running Linux than compiling the kernel and other software from scratch, enabling users with minimal computer knowledge to run a Linux system.
References
- ↑ 1.0 1.1 Linus' first USENET post concerning Linux (Retrieved 07-April-2007).
- ↑ LINUX's History by Linus Torvalds (Retrieved 07-April-2007).
- ↑ March 2007 Web Server Survey. Netcraft (2007-03).