LQWiki - User contributions [en]

Mbox

2006-07-31T00:48:37Z

Frob23:

'''mbox''' is a single file format for storing [[mail]] messages. It is often considered to have been made obsolete by [[maildir]]. Because it stores all the messages in one file, there is a possibility of corruption when two different programs try and edit the file at the same time.

The format of the file is simple. Each message starts with the five characters "''From ''" and ends with an extra blank line at the bottom. This lets mail programs easily find the start of the next message by looking for those five characters preceded by a newline. Little else is done to format or store the message other than dumping the raw contents into the file. There is one exception to the general rule of not changing a message. If the message has a line which starts with "''From ''" in the body, it will usually add a character in front of that, typically ">", to prevent the mail clients, [[MUA]], from becoming confused and thinking a new message is starting.

[[Category:Mail]]

{{stub}}

Mbox

2006-07-31T00:47:51Z

Frob23:

'''mbox''' is a single file format for storing [[mail]] messages. It is often considered to have been made obsolete by [[maildir]]. Because it stores all the messages in one file, there is a possibility of corruption when two different programs try and edit the file at the same time.

The format of the file is simple. Each message starts with the five characters "''From ''" and ends with an extra blank line at the bottom. This lets mail programs easily find the start of the next message by looking for those five characters preceded by a newline. Little else is done to format or store the message other than dumping the raw contents into the file. There is one exception to the general rule of not changing a message. If the message has a line which starts with "''From ''" in the body, it will usually add a character in front of that, typically ">" to prevent the mail clients, [[MUA]], from becoming confused and thinking a new message is starting.

[[Category:Mail]]

{{stub}}

Mbox

2006-07-31T00:46:47Z

Frob23:

'''mbox''' is a single file format for storing [[mail]] messages. It is often considered to have been made obsolete by [[maildir]]. Because it stores all the messages in one file, there is a possibility of corruption when two different programs try and edit the file at the same time.

The format of the file is simple. Each message starts with the five characters ''From '' and ends with an extra blank line at the bottom. This lets mail programs easily find the start of the next message by looking for those five characters preceded by a newline. Little else is done to format or store the message other than dumping the raw contents into the file. There is one exception to the general rule of not changing a message. If the message has a line which starts with ''From '' in the body, it will usually add a character in front of that, typically ''>'' to prevent the mail clients, [[MUA]], from becoming confused and thinking a new message is starting.

[[Category:Mail]]

{{stub}}

User talk:Frob23

2005-03-05T05:03:14Z

Frob23:

An action of mindless fiddling with something (usually physical). This is the root word from which [[User:Frob23|Frob23]] gets his user-name.

It's good to link from userpages to regular pages, not so good the other way around. Here's your stuff. You might want to modify it and put it on your userpage. [[User:Crazyeddie|Crazyeddie]] 13:54, Jan 17, 2005 (EST)

----
Done. Oops... that's embarrassing. I didn't mean it to be like a vanity thing. Just wanted to add that page and didn't know what to say near the top.

Anyway... it won't happen again. I'm trying to find some place where I can add some information to these pages but so far most areas where I would add something are filled out.

I'm sure there is something. I just have to find it.

--[[User:Frob23|Frob23]] 22:29, Jan 20, 2005 (EST)

Nice to see a fellow rambler. Do you want to take over the Jargon project? I'll help out when I can, and try to give you pointers on how to be trantic about it. One thing I've been meaning to do is replace the attribution notices on the Jargon pages with a template, so we can change the notice later on. But that is a ''lot'' of tedium. [[User:Crazyeddie|Crazyeddie]] 14:46, Jan 21, 2005 (EST)

----

I don't know that I would be ready to take over the Jargon project but I would be more than willing to help. The world of wiki is still new to me (last one I remember contributing to was the Plan9 one several years ago and it was all plain text additions). I had no idea about this one until just a little while ago and decided to see if I could contribute anything.

Like I said, I don't know very much about the wiki when it comes to formatting or anything. Or how a template would work. But if you created one (or gave me a clue as to how to create one myself) I would bounce around the pages that currently exist, in my free time, and replace the old attribution with the new template.

I think I am probably going to spend a good amount of time when I get to work tonight learning the markup used by this wiki and then browsing the entries to see which ones look good and why. In the time I have spent hopping around I have seen a number of pages which look fantastic... and others which don't look bad but could look better.

--[[User:Frob23|Frob23]] 17:01, Jan 21, 2005 (EST)

Here's a link to a wikicode guide: [[LQWiki:Wiki markup]] And our manual of style (which I haven't really read myself): [[LQWiki:Manual of Style]] We probably ought to come up with a templated welcome message, like the mods at Wikipedia have. [[User:Crazyeddie|Crazyeddie]] 17:13, Jan 21, 2005 (EST)

Okay, I've made the template. If I got things right, you just need to replace the attribution notices with this: <nowiki>{{Jargon File/Attribution}}</nowiki>, which the wiki software should intepret as:

{{Jargon File/Attribution}}

(Got it right on the second try.) It'll save time if you go through the [[List of Jargon File Entries]] in order. Not as fun as random bouncing, but more efficient. [[User:Crazyeddie|Crazyeddie]] 17:34, Jan 21, 2005 (EST)

----

Cool, you just gave me something to do all night while at work. Better then staring at the wall. I've tested it out on one entry already and it works great.

[[User:Frob23|Frob23]] 18:04, Jan 21, 2005 (EST)

about your note to self - /s play merry hell with the wiki software. [[User:Crazyeddie|Crazyeddie]] 18:10, Jan 21, 2005 (EST)

----

I see that... the note really means to check if the redirect contains material from the Jargon file which I believe it does but I did not see any attribution on the page. I gotcha about the starting / ... although the redirect seems to manage some magic and found a way to do it. Maybe the redirect page isn't needed? I don't know. I was going to finish out the stuff before A and then go take a peek at it.

It looks like the dev/null article was made by somebody else, and the Jargon File doesn't really have anything to add. No attrib needed. [[User:Crazyeddie|Crazyeddie]] 18:50, Jan 21, 2005 (EST)

I'm pretty much the only one who has done anything with the Jargon File, and I've been pretty careful about attribution. So if there isn't an attribution notice of some sort already there, chances are there isn't one needed. Either someone got there first, and the File didn't have anything useful to add, or the Jargon material was edited out later. You're welcome to double check if you wish. [[User:Crazyeddie|Crazyeddie]] 02:43, Jan 23, 2005 (EST)

----

I'm trying to make doubly sure just in case -- it only takes a second and I am there anyway. If I see three or more sentences which are directly from the Jargon file, I am going to assume an attribution is needed. This is easier when the quoted text includes other jargon. In cases where I am unsure and it is very general, I'll just go along my way. I've seen a couple like that. I only add it to the talk when it is either likely it is there but too general to know if someone came up with it originally or like BASIC where there is a custom attribution to the history of it having jargon content but there isn't anymore.

Note: I think there have been maybe two were I honestly added an attribution where there wasn't one before. Most of it is like the [[code grinder]] entry where it talks about the Jargon file but doesn't include a formal attribute line.

--[[User:Frob23|Frob23]] 02:53, Jan 23, 2005 (EST)

Now that you're done with the notice grunt work, you might want to start adding more entries. A good place to start would be the "Wanted Pages" list (located on the left nav bar under "Special Pages"). Go through those first before going through the Jargon list alphabetically.

You'll have to tweak the entries a little. The File is set up like a dictionary, wikis are more like encylopedias. The convention in wikis is to use the name of the article in the first sentence and to bold it there. Try to rewrite the entry so it doesn't use a numbered list. When you cut and paste entries from the Jargon website, you'll notice that the paragraphs have an inital indent. There is some sort of formatting mojo in the indent, so delete it or it will screw up the format of the wiki page.

I'll be looking over your sholder, at least at first, so I'll try to catch any mistakes.

The "in part" bit of the attribution notice is there in case somebody adds material to an article that was originally a cut-and-paste from the File. I think we should use it only if the article is 50%+ Jargon material. Otherwise, I think we can get by with footnote style links. 16:02, Feb 16, 2005 (EST)

----

It will probably be a while before I really have time to add anything. I have gotten bogged down with school and other outside stuff which requires my immediate attention.

As I get around to it, I will try and add some stuff.

-[[User:Frob23|Frob23]] 00:03, Mar 5, 2005 (EST)

Jargon File

2005-02-14T07:35:50Z

Frob23: /* The Jargon File and this Wiki */

The '''Jargon File''' is a dictionary of common computer lingo (the "jargon"). It is quite funny in many places, though slightly out of date in others. It is also known as The Hacker's Dictionary, or the Hacker's Jargon File. It is public domain, but the authors request attribution. The current incarnation is maintained by [[ESR|Eric S Raymond]], and is located here: http://www.catb.org/jargon/ In addition to the glossary of hacker terms which forms the bulk of the file, there are several longer pieces in various appendices.

*[[TV Typewriters]]
*[[Magic]]
*[[AI Koans]]
*[[OS and JEDGAR]]
*[[Story of Mel]]

==The Jargon File and this Wiki==
Since the Jargon File is in the public domain, entries from the Jargon File can be incorporated into this wiki at will. Keep in mind that the authors of the Jargon File request attribution.

The creators of the File assumed that the reader had some knowledge of the technical meaning of the terms. Also, the File focuses on humor rather than information. Subjects that are the basis of [[holy wars]] are explained in a provocative manner, to increase entertainment value, so it is a good idea to edit LQwiki incorporated entries with an eye towards NPOV (neutral point of view). Despite all of this, the File does serve a purpose here. It provides a starting point that LQwiki contributors can build on, which prevents us from having to reinvent the wheel. Also, the file, which was started in the [[elder days]] provides insight into the [[hacker]] culture which created Linux, and its [[history]].

If you wish to help incorporate the Jargon File into this wiki, it is advised that you concentrate on incorporating Jargon material into existing articles first, and then creating new articles from the [[Special:Wantedpages]] list. This will help to ensure that the incorporated entries are on topic.

To add the appropriate attribution to an entry with information from the Jargon File, please include the following:

<nowiki>{{Jargon File/Attribution}}</nowiki>

This will produce "{{Jargon File/Attribution}}"

*[[Jargon File/Attribution|Attribution template]]
*[[List of Jargon File Entries]]

==History of the Jargon File==
''This section comes from the revision history chapter of the Jargon File.'' http://www.catb.org/jargon/html/revision-history.html

The original Jargon File was a collection of [[hacker]] jargon from technical cultures including the [[MIT]] AI Lab, the Stanford AI lab ([[SAIL]]), and others of the old [[ARPANET]] AI/[[LISP]]/[[PDP-10]] communities including Bolt, Beranek and Newman (BBN), Carnegie-Mellon University (CMU), and Worcester Polytechnic Institute (WPI).

The Jargon File (hereafter referred to as ‘jargon-1’ or ‘the File’) was begun by Raphael Finkel at Stanford in 1975. From this time until the plug was finally pulled on the [[SAIL]] computer in 1991, the File was named AIWORD.RF[UP,DOC] there. Some terms in it date back considerably earlier ([[frob]] and some senses of [[moby]], for instance, go back to the [[Tech Model Railroad Club]] at MIT and are believed to date at least back to the early 1960s). The revisions of jargon-1 were all unnumbered and may be collectively considered ‘Version 1’.

In 1976, Mark Crispin, having seen an announcement about the File on the SAIL computer, FTPed a copy of the File to MIT. He noticed that it was hardly restricted to ‘AI words’ and so stored the file on his directory as AI:MRC;SAIL JARGON.

The file was quickly renamed JARGON > (the ‘>’ caused versioning under [[ITS]]) as a flurry of enhancements were made by Mark Crispin and Guy L. Steele Jr. Unfortunately, amidst all this activity, nobody thought of correcting the term ‘jargon’ to ‘slang’ until the compendium had already become widely known as the Jargon File.

Raphael Finkel dropped out of active participation shortly thereafter and Don Woods became the SAIL contact for the File (which was subsequently kept in duplicate at SAIL and MIT, with periodic resynchronizations).

The File expanded by fits and starts until about 1983; [[Richard Stallman]] was prominent among the contributors, adding many [[MIT]] and [[ITS]]-related coinages.

In Spring 1981, a hacker named Charles Spurgeon got a large chunk of the File published in Stewart Brand's CoEvolution Quarterly (issue 29, pages 26—35) with illustrations by Phil Wadler and Guy Steele (including a couple of the Crunchly cartoons). This appears to have been the File's first paper publication. (The version of the File located at http://www.catb.org/jargon/ includes the Crunchly cartoons.)

A late version of jargon-1, expanded with commentary for the mass market, was edited by Guy Steele into a book published in 1983 as The Hacker's Dictionary (Harper & Row CN 1082, ISBN 0-06-091082-8). The other jargon-1 editors (Raphael Finkel, Don Woods, and Mark Crispin) contributed to this revision, as did [[Richard M. Stallman]] and Geoff Goodfellow. This book (now out of print) is hereafter referred to as ‘Steele-1983’ and those six as the Steele-1983 coauthors.

Shortly after the publication of Steele-1983, the File effectively stopped growing and changing. Originally, this was due to a desire to freeze the file temporarily to facilitate the production of Steele-1983, but external conditions caused the ‘temporary’ freeze to become permanent.

The AI Lab culture had been hit hard in the late 1970s by funding cuts and the resulting administrative decision to use vendor-supported hardware and software instead of homebrew whenever possible. At MIT, most AI work had turned to dedicated [[LISP]] Machines. At the same time, the commercialization of AI technology lured some of the AI Lab's best and brightest away to startups along the Route 128 strip in Massachusetts and out West in Silicon Valley. The startups built LISP machines for MIT; the central MIT-AI computer became a [[TWENEX]] system rather than a host for the AI hackers' beloved [[ITS]].

The Stanford AI Lab had effectively ceased to exist by 1980, although the [[SAIL]] computer continued as a Computer Science Department resource until 1991. Stanford became a major TWENEX site, at one point operating more than a dozen [[TOPS-20]] systems; but by the mid-1980s most of the interesting software work was being done on the emerging [[BSD]] [[Unix]] standard.

In April 1983, the [[PDP-10]]-centered cultures that had nourished the File were dealt a death-blow by the cancellation of the Jupiter project at Digital Equipment Corporation. The File's compilers, already dispersed, moved on to other things. Steele-1983 was partly a monument to what its authors thought was a dying tradition; no one involved realized at the time just how wide its influence was to be.

By the mid-1980s the File's content was dated, but the legend that had grown up around it never quite died out. The book, and softcopies obtained off the [[ARPANET]], circulated even in cultures far removed from MIT and Stanford; the content exerted a strong and continuing influence on hacker language and humor. Even as the advent of the microcomputer and other trends fueled a tremendous expansion of hackerdom, the File (and related materials such as the [[Some AI Koans]] in Appendix A) came to be seen as a sort of sacred epic, a hacker-culture Matter of Britain chronicling the heroic exploits of the Knights of the Lab. The pace of change in hackerdom at large accelerated tremendously — but the Jargon File, having passed from living document to icon, remained essentially untouched for seven years.

This revision contains nearly the entire text of a late version of jargon-1 (a few obsolete PDP-10-related entries were dropped after careful consultation with the editors of Steele-1983). It merges in about 80% of the Steele-1983 text, omitting some framing material and a very few entries introduced in Steele-1983 that are now also obsolete.

The http://www.catb.org/jargon/ version casts a wider net than the old Jargon File; its aim is to cover not just AI or PDP-10 hacker culture but all the technical computing cultures wherein the true hacker-nature is manifested. More than half of the entries now derive from [[Usenet]] and represent jargon now current in the [[C]] and [[Unix]] communities, but special efforts have been made to collect jargon from other cultures including [[IBM]] [[PC]] programmers, [[Amiga]] fans, [[Mac]] enthusiasts, and even the IBM [[mainframe]] world.

[[Eric S. Raymond]] maintains the new File with assistance from Guy L. Steele Jr.; these are the persons primarily reflected in the File's editorial ‘we’, though the editors take pleasure in acknowledging the special contribution of the other coauthors of Steele-1983.

The 2.9.6 version became the main text of The New Hacker's Dictionary, by Eric Raymond (ed.), MIT Press 1991, ISBN 0-262-68069-6.

The 3.0.0 version was published in August 1993 as the second edition of The New Hacker's Dictionary, again from MIT Press (ISBN 0-262-18154-1).

The 4.0.0 version was published in September 1996 as the third edition of The New Hacker's Dictionary from MIT Press (ISBN 0-262-68092-0).

The maintainers are committed to updating the on-line version of the Jargon File through and beyond paper publication, and will continue to make it available to archives and public-access sites as a trust of the hacker community.

==See also==
*[[Humor]]
*[[History of unix]]

==External links==
*[http://www.catb.org/jargon/ Jargon File resources]

User:Frob23

2005-02-14T07:29:20Z

Frob23:

=frob23=

Often known in real life and in virtual life as Eric Fenderson, although neither of those are included in his actual given name. Eric Fenderson is obsessed with Unix in all its forms. He swears each night before falling off to sleep that he will, one day, port V7 to modern hardware.

[[Frob]] is an action of mindless fiddling with something (usually physical). This is the root word from which I take my user-name. I've used it for a long, long time mainly because a lot of my computer activities were mindless fiddling. Stuff like adding a password to command.com or changing the commands DOS used. Mindless stuff which I continued to do when I moved on to real operating systems. The wonderful thing about frobbing is that often you learn a lot by playing around without intending to learn anything from it.

I spent three years working towards a computer engineering major before I realized that it was not for me. Surprisingly (to myself at the time) my experience with Linux benefited me in that major because all of the work was done on *nix machines. I found [[FreeBSD]] during that time and have been using it steadily ever since but I still have an affection for Linux... she was my first.

I like the wiki and would add more but most of the areas where I could add information would be in the Jargon definitions. And, as it has been pointed out, it is important to not allow them to overwhelm the real information this wiki contains. There are good online sources for the Jargon file.

I have been obsessed with [[Hacker]] [[jargon]] and information ever since I found a hard copy of The New Hacker's Dictionary (version 1) at a local library. This was many years ago but I remember it gave me a vision of something deeper in the mindless tooling around with computers I was doing. I have since obtained hard copies of it and the two subsequent versions for myself. And, when the library moved across town, I was even able to purchase the worn original for $4.00 from the library because they were going to throw it out.

Almost accidentally, I have found myself fitting the description of a Hacker from the appendix. Right down to being a Theater Technician -- which at the time was something I decided to do to avoid the stereotype I saw myself fitting.

So, anyway, clearly I would love to share the source with those who are coming behind and don't know the joy. When I first heard the -[[P convention]] in real life it brought a smile to my face. It made me realize that I am part of a tradition that came before me and will go on beyond me. I want to share that with others.

Well, that's a rambling user page.

--[[User:Frob23|Frob23]] 22:26, Jan 20, 2005 (EST)

Recent Update: Okay, all the old attributions on Jargon Entries have been changed to the new template. Hopefully I didn't miss anything and people will use the new format. I also spent a little time trying to ensure a somewhat consistent format with the placement of the attribution -- I am sure I have failed. But, in general, I have tried to keep it toward the bottom of the article (unless it more clearly belonged right below the block of text from the Jargon file) and above the STUB notice -- as I think the stub warning should be the absolute last thing in an article.
[[User:Frob23|Frob23]] 02:29, Feb 14, 2005 (EST)

User:Frob23

2005-02-14T07:29:00Z

Frob23: update

Zork

2005-02-14T07:24:30Z

Frob23: Changed text attribution to template.

'''Zork''' was the second of the great early experiments in computer fantasy gaming; see [[ADVENT]]. Originally written on MIT-DM during 1977-1979, later distributed with [[BSD]] Unix (as a patched, sourceless RT-11 [[FORTRAN]] [[binary]]; see [[retrocomputing]]) and commercialized as ‘The Zork Trilogy’ by Infocom. The FORTRAN source was later rewritten for portability and released to [[Usenet]] under the name “Dungeon”. Both FORTRAN “Dungeon” and translated [[C]] versions are available at many [[FTP]] sites; the commercial Zork trilogy is available at http://www.ifarchive.org/ . See also [[grue]]. You can play Zork via a [[Java]] [[Applet]][http://www.forkexec.com/html/play-zork1.html].

{{Jargon File/Attribution}}

MUD

2005-02-14T07:07:23Z

Frob23: Changed text attribution to template.

'''MUD''' stands for '''M'''ulti-'''U'''ser '''D'''ungeon or '''M'''ulti-'''U'''ser '''D'''imension. It can refer to:

#A class of virtual reality experiments accessible via the Internet. These are real-time chat forums with structure; they have multiple ‘locations’ like an adventure game, and may include combat, traps, puzzles, magic, a simple economic system, and the capability for characters to build more structure onto the database that represents the existing world.
#vi. To play a MUD. The acronym MUD is often lowercased and/or verbed; thus, one may speak of going mudding, etc.

Historically, MUDs (and their more recent progeny with names of MU- form) derive from a hack by Richard Bartle and Roy Trubshaw on the University of Essex's DEC-10 in the early 1980s; descendants of that game still exist today and are sometimes generically called BartleMUDs. There is a widespread myth (repeated, unfortunately, by earlier versions of this lexicon) that the name MUD was trademarked to the commercial MUD run by Bartle on British Telecom (the motto: “You haven't lived 'til you've died on MUD!”); however, this is false — Richard Bartle explicitly placed ‘MUD’ in the [[public domain]] in 1985. BT was upset at this, as they had already printed [[trademark]] claims on some maps and posters, which were released and created the myth.

Students on the European academic networks quickly improved on the MUD concept, spawning several new MUDs (VAXMUD, AberMUD, LPMUD). Many of these had associated bulletin-board systems for social interaction. Because these had an image as ‘research’ they often survived administrative hostility to [BBS]]s in general. This, together with the fact that [[Usenet]] feeds were often spotty and difficult to get in the U.K., made the MUDs major foci of [[hacker|hackish]] social interaction there.

AberMUD and other variants crossed the Atlantic around 1988 and quickly gained popularity in the U.S.; they became nuclei for large [[hacker]] communities with only loose ties to traditional hackerdom (some observers see parallels with the growth of [[Usenet]] in the early 1980s). The second wave of MUDs (TinyMUD and variants) tended to emphasize social interaction, puzzles, and cooperative world-building as opposed to combat and competition (in writing, these social MUDs are sometimes referred to as ‘MU*’, with ‘MUD’ implicitly reserved for the more game-oriented ones). By 1991, over 50% of MUD sites were of a third major variety, LPMUD, which synthesizes the combat/puzzle aspects of AberMUD and older systems with the extensibility of TinyMud. In 1996 the cutting edge of the technology is Pavel Curtis's MOO, even more extensible using a built-in object-oriented language. The trend toward greater programmability and flexibility will doubtless continue.

The state of the art in MUD design is still moving very rapidly, with new simulation designs appearing (seemingly) every month. Around 1991 there was an unsuccessful movement to deprecate the term MUD itself, as newer designs exhibit an exploding variety of names corresponding to the different simulation styles being explored. It survived. See also [[bonk]]/[[oif]], [[FOD]], [[link-dead]], [[mudhead]], [[talk mode]].

{{Jargon File/Attribution}}

Linux

2005-02-14T07:03:13Z

Frob23: Changed text attribution to template.

'''Linux''' is the popular [[kernel]] the heart of the [[operating system]] sometimes called [[GNU/Linux]]. It was initially programmed by the famous Finnish programmer [[Linus Torvalds]], and was first released in 1991. Nowadays, though still led by Linus, programmers all over the world participate in its ongoing development.

Its mascot is a penguin called [[Tux]].

According to the [[Jargon File]], "Linux is what [[GNU]] aimed to be, and it relies on the GNU toolset. But the [[Free Software Foundation]] didn't produce the kernel to go with that toolset until 1999, which was too late. Other, similar efforts like [[FreeBSD]] and [[NetBSD]] have been technically successful but never caught fire the way Linux has; as this is written in 2003, Linux has effectively swallowed all [[proprietary]] [[Unix]]es except [[Solaris]] and is seriously challenging [[Microsoft]]. It has already captured 41% of the Internet-server market and over 25% of general business servers."

One of the reasons for Linux's success is the [[bazaar]] effect, opening the development to as many [[hacker]]s as possible. By contrast, although the GNU Project's [[HURD]] kernel was [[libre]], the actual development team was closed, to the point, as one observer put it, of intellectual incest. It is not a coincidence that development of Linux started just after the [[Great Internet Explosion]], it was the rise of the internet that enabled bazaar-style development to occur.

==Attributions==
{{Jargon File/Attribution}}

* [http://www.catb.org/jargon/html/L/Linux.html Jargon File entry on Linux]

==External links==

* [http://www.kernel.org The Linux Kernel Project]
* [http://www.kerneltrap.org KernelTrap] - Latest news on *NIX kernel development

Hello world

2005-02-14T06:52:46Z

Frob23: Changed text attribution to template.

'''Hello World''' is any of the minimal programs that emit this message (a representative sample in various languages can be found at http://www.latech.edu/~acm/helloworld/ ). The purpose of the program is to print "Hello, World!" to the [[standard output]], and it is generally the first program a [[programming]] student learns. The tradition comes from the [[C]] programming language, and it is the first example program in [[K&R]]. If you can get a hello world program to run, you know at least that you have the programming tools properly installed and can move on from there.

Environments that generate an unreasonably large executable for this trivial test or which require a hairy [[compiler]]-[[linker]] invocation to generate it are considered to [[lose]].

===Examples===
*[[Hello World in C]]

==See also==
*[[Hello sailor!]]

{{Jargon File/Attribution}}

HAKMEM

2005-02-14T06:51:50Z

Frob23: Changed text attribution to template.

'''HAKMEM''', aka MIT AI Memo 239 (February 1972), is a legendary collection of neat mathematical and programming [[hack]]s contributed by many people at MIT and elsewhere. (The title of the memo really is “HAKMEM”, which is a 6-letterism for ‘hacks memo’.) Some of them are very useful techniques, powerful theorems, or interesting unsolved problems, but most fall into the category of mathematical and computer trivia. Here is a sampling of the entries (with authors), slightly paraphrased:

*Item 41 (Gene Salamin): There are exactly 23,000 prime numbers less than 2^18.

*Item 46 (Rich Schroeppel): The most probable suit distribution in bridge hands is 4-4-3-2, as compared to 4-3-3-3, which is the most evenly distributed. This is because the world likes to have unequal numbers: a thermodynamic effect saying things will not be in the state of lowest energy, but in the state of lowest disordered energy.

*Item 81 (Rich Schroeppel): Count the magic squares of order 5 (that is, all the 5-by-5 arrangements of the numbers from 1 to 25 such that all rows, columns, and diagonals add up to the same number). There are about 320 million, not counting those that differ only by rotation and reflection.

*Item 154 (Bill Gosper): The myth that any given programming language is machine independent is easily exploded by computing the sum of powers of 2. If the result loops with period = 1 with sign +, you are on a sign-magnitude machine. If the result loops with period = 1 at -1, you are on a twos-complement machine. If the result loops with period greater than 1, including the beginning, you are on a ones-complement machine. If the result loops with period greater than 1, not including the beginning, your machine isn't binary — the pattern should tell you the base. If you run out of memory, you are on a string or bignum system. If arithmetic overflow is a fatal error, some fascist pig with a read-only mind is trying to enforce machine independence. But the very ability to trap overflow is machine dependent. By this strategy, consider the universe, or, more precisely, algebra: Let X = the sum of many powers of 2 = ...111111 (base 2). Now add X to itself: X + X = ...111110. Thus, 2X = X - 1, so X = -1. Therefore algebra is run on a machine (the universe) that is two's-complement.

*Item 174 (Bill Gosper and Stuart Nelson): 21963283741 is the only number such that if you represent it on the [[PDP-10]] as both an integer and a floating-point number, the bit patterns of the two representations are identical.

*Item 176 (Gosper): The “[[banana problem|banana phenomenon]]” was encountered when processing a character string by taking the last 3 letters typed out, searching for a random occurrence of that sequence in the text, taking the letter following that occurrence, typing it out, and iterating. This ensures that every 4-letter string output occurs in the original. The program typed BANANANANANANANA.... We note an ambiguity in the phrase, “the Nth occurrence of.” In one sense, there are five 00's in 0000000000; in another, there are nine. The editing program TECO finds five. Thus it finds only the first ANA in BANANA, and is thus obligated to type N next. By Murphy's Law, there is but one NAN, thus forcing A, and thus a loop. An option to find overlapped instances would be useful, although it would require backing up N − 1 characters before seeking the next N-character string.

Note: This last item refers to a [[Dissociated Press]] implementation. See also [[banana problem]].

HAKMEM also contains some rather more complicated mathematical and technical items, but these examples show some of its fun flavor.

An HTML transcription of the entire document is available at http://www.inwap.com/pdp10/hbaker/hakmem/hakmem.html.

{{Jargon File/Attribution}}

Hacker

2005-02-14T06:50:11Z

Frob23: Changed text attribution to template.

'''Hacker''' is someone who [[hack]]s, and originally meant someone who makes furniture with an axe.

Here is a list of modern day uses of this word:

#A person who enjoys exploring the details of programmable systems and how to stretch their capabilities, as opposed to most users, who prefer to learn only the minimum necessary. [[RFC]]1392, the Internet Users' Glossary, usefully amplifies this as: A person who delights in having an intimate understanding of the internal workings of a system, computers and computer networks in particular.
#One who programs enthusiastically (even obsessively) or who enjoys [[programming]] rather than just theorizing about programming.
#A person capable of appreciating [[hack value]].
#A person who is good at programming quickly.
#An expert at a particular program, or one who frequently does work using it or on it; as in ‘a Unix hacker’. (Definitions 1 through 5 are correlated, and people who fit them congregate.)
#An expert or enthusiast of any kind. One might be an astronomy hacker, for example.
#One who enjoys the intellectual challenge of creatively overcoming or circumventing limitations.
#([[deprecated]]) A malicious meddler who tries to discover sensitive information by poking around. Hence password hacker, network hacker. The correct term for this sense is [[cracker]].

The term ‘hacker’ also tends to connote membership in the global community defined by the net (see [[the network]]. For discussion of some of the basics of this culture, see [[ESR]]'s column, "[http://www.catb.org/~esr/faqs/hacker-howto.html How to Become a Hacker]". It also implies that the person described is seen to subscribe to some version of the [[hacker ethic]].

It is better to be described as a hacker by others than to describe oneself that way. Hackers consider themselves something of an elite (a meritocracy based on ability), though one to which new members are gladly welcome. There is thus a certain ego satisfaction to be had in identifying yourself as a hacker (but if you claim to be one and are not, you'll quickly be labeled [[bogus]]). See also [[geek]], [[wannabee]].

This term seems to have been first adopted as a badge in the 1960s by the hacker culture surrounding [[TMRC]] and the MIT AI Lab. We have a report that it was used in a sense close to this entry's by teenage radio hams and electronics tinkerers in the mid-1950s.

===A Portrait of J. Random Hacker===
This profile reflects detailed comments on an earlier ‘trial balloon’ version from about a hundred [[Usenet]] respondents. Where comparatives are used, the implicit ‘other’ is a randomly selected segment of the non-hacker population of the same size as hackerdom.

An important point: Except in some relatively minor respects such as slang vocabulary, hackers don't get to be the way they are by imitating each other. Rather, it seems to be the case that the combination of personality traits that makes a hacker so conditions one's outlook on life that one tends to end up being like other hackers whether one wants to or not (much as bizarrely detailed similarities in behavior and preferences are found in genetic twins raised separately).

====General Apperance====
Intelligent. Scruffy. Intense. Abstracted. Surprisingly for a sedentary profession, more hackers run to skinny than fat; both extremes are more common than elsewhere. Tans are rare.

====Dress====
Casual, vaguely post-hippie; T-shirts, jeans, running shoes, Birk-enstocks (or bare feet). Long hair, beards, and moustaches are common. High incidence of tie-dye and intellectual or humorous ‘slogan’ T-shirts. Until the mid-1990s such T-shirts were seldom computer-related, as that would have been too obvious — but the hacker culture has since developed its own icons, and J. Random Hacker now often wears a [[Tux|Linux penguin]] or [[BSD]] daemon or a [[DeCSS]] protest shirt.

A substantial minority prefers ‘outdoorsy’ clothing — hiking boots (“in case a mountain should suddenly spring up in the machine room”, as one famous parody put it), khakis, lumberjack or chamois shirts, and the like.

After about 1995 hacker dress styles assimilated some influence from punk, gothic, and rave subcultures. This was relatively mild and has manifested mostly as a tendency to wear a lot of black, especially when ‘dressed up’ to the limit of formality. Other markers of those subcultures such as piercings, chains, and dyed hair remain relatively uncommon. Hackers appear to wear black more because it goes with everything and hides dirt than because they want to look like goths.

Very few hackers actually fit the National Lampoon Nerd stereotype, though it lingers on at MIT and may have been more common before 1975. At least since the late Seventies backpacks have been more common than briefcases, and the hacker ‘look’ has been more whole-earth than whole-polyester.

Hackers dress for comfort, function, and minimal maintenance hassles rather than for appearance (some, perhaps unfortunately, take this to extremes and neglect personal hygiene). They have a very low tolerance of suits and other ‘business’ attire; in fact, it is not uncommon for hackers to quit a job rather than conform to a dress code. When they are somehow backed into conforming to a dress code, they will find ways to subvert it, for example by wearing absurd novelty ties.

Female hackers almost never wear visible makeup, and many use none at all.

====Reading Habits====
Omnivorous, but usually includes lots of science and science fiction. The typical hacker household might subscribe to Analog, Scientific American, Whole-Earth Review, and Smithsonian (most hackers ignore Wired and other self-consciously ‘[[cyberpunk]]’ magazines, considering them [[wannabee]] fodder). Hackers often have a reading range that astonishes liberal arts people but tend not to talk about it as much. Many hackers spend as much of their spare time reading as the average American burns up watching TV, and often keep shelves and shelves of well-thumbed books in their homes.

====Other Interests====
Some hobbies are widely shared and recognized as going with the culture: science fiction, music, medievalism (in the active form practiced by the Society for Creative Anachronism and similar organizations), chess, go, backgammon, wargames, and intellectual games of all kinds. (Role-playing games such as Dungeons and Dragons used to be extremely popular among hackers but they lost a bit of their luster as they moved into the mainstream and became heavily commercialized. More recently, Magic: The Gathering has been widely popular among hackers.) Logic puzzles. Ham radio. Other interests that seem to correlate less strongly but positively with hackerdom include linguistics and theater teching.

====Physical Activity and Sports====
Many (perhaps even most) hackers don't follow or do sports at all and are determinedly anti-physical. Among those who do, interest in spectator sports is low to non-existent; sports are something one does, not something one watches on TV.

Further, hackers avoid most team sports like the plague. Volleyball was long a notable exception, perhaps because it's non-contact and relatively friendly; Ultimate Frisbee has become quite popular for similar reasons. Hacker sports are almost always primarily self-competitive ones involving concentration, stamina, and micromotor skills: martial arts, bicycling, auto racing, kite flying, hiking, rock climbing, aviation, target-shooting, sailing, caving, juggling, skiing, skating, skydiving, scuba diving. Hackers' delight in techno-toys also tends to draw them towards hobbies with nifty complicated equipment that they can tinker with.

The popularity of martial arts in the hacker culture deserves special mention. Many observers have noted it, and the connection has grown noticeably stronger over time. In the 1970s, many hackers admired martial arts disciplines from a distance, sensing a compatible ideal in their exaltation of skill through rigorous self-discipline and concentration. As martial arts became increasingly mainstreamed in the U.S. and other western countries, hackers moved from admiring to doing in large numbers. In 1997, for example, your humble editor recalls sitting down with five strangers at the first Perl conference and discovering that four of us were in active training in some sort of martial art — and, what is more interesting, nobody at the table found this high perecentage at all odd.

Today (2000), martial arts seems to have become firmly established as the hacker exercise form of choice, and the martial-arts culture combining skill-centered elitism with a willingness to let anybody join seems a stronger parallel to hacker behavior than ever. Common usages in hacker slang un-ironically analogize programming to [[kung fu]] (thus, one hears talk of “code-fu” or in reference to specific skills like “HTML-fu”). Albeit with slightly more irony, today's hackers readily analogize assimilation into the hacker culture with the plot of a Jet Li movie: the aspiring newbie studies with masters of the tradition, develops his art through deep meditation, ventures forth to perform heroic feats of hacking, and eventually becomes a master who trains the next generation of newbies in the hacker way.

====Education====
Nearly all hackers past their teens are either college-degreed or self-educated to an equivalent level. The self-taught hacker is often considered (at least by other hackers) to be better-motivated, and may be more respected, than his school-shaped counterpart. Academic areas from which people often gravitate into hackerdom include (besides the obvious computer science and electrical engineering) physics, mathematics, linguistics, and philosophy.

====Things Hackers Detest and Avoid====
All the works of [[Microsoft]]. Smurfs, Ewoks, and other forms of offensive cuteness. Bureaucracies. Stupid people. Easy listening music. Television (with occasional exceptions for cartoons, movies, and good SF like Star Trek classic or Babylon 5). Business suits. Dishonesty. Incompetence. Boredom. [[COBOL]]. [[BASIC]]. Character-based menu interfaces.

====Food====
Ethnic. Spicy. Oriental, esp. Chinese and most esp. Szechuan, Hunan, and Mandarin (hackers consider Cantonese vaguely déclassé). Hackers prefer the exotic; for example, the Japanese-food fans among them will eat with gusto such delicacies as fugu (poisonous pufferfish) and whale. Thai food has experienced flurries of popularity. Where available, high-quality Jewish delicatessen food is much esteemed. A visible minority of Southwestern and Pacific Coast hackers prefers Mexican.

For those all-night hacks, pizza and microwaved burritos are big. Interestingly, though the mainstream culture has tended to think of hackers as incorrigible junk-food junkies, many have at least mildly health-foodist attitudes and are fairly discriminating about what they eat. This may be generational; anecdotal evidence suggests that the stereotype was more on the mark before the early 1980s.

====Politics====
Formerly vaguely liberal-moderate, more recently moderate-to-neoconservative (hackers too were affected by the collapse of socialism). There is a strong libertarian contingent which rejects conventional left-right politics entirely. The only safe generalization is that hackers tend to be rather anti-authoritarian; thus, both paleoconservatism and ‘hard’ leftism are rare. Hackers are far more likely than most non-hackers to either (a) be aggressively apolitical or (b) entertain peculiar or idiosyncratic political ideas and actually try to live by them day-to-day.

====Gender and Ethnicity====
Hackerdom is still predominantly male. However, the percentage of women is clearly higher than the low-single-digit range typical for technical professions, and female hackers are generally respected and dealt with as equals.

In the U.S., hackerdom is predominantly Caucasian with strong minorities of Jews (East Coast) and Orientals (West Coast). The Jewish contingent has exerted a particularly pervasive cultural influence (see Food, above, and note that several common jargon terms are obviously mutated Yiddish).

The ethnic distribution of hackers is understood by them to be a function of which ethnic groups tend to seek and value education. Racial and ethnic prejudice is notably uncommon and tends to be met with freezing contempt.

When asked, hackers often ascribe their culture's gender- and color-blindness to a positive effect of text-only network channels, and this is doubtless a powerful influence. Also, the ties many hackers have to AI research and SF literature may have helped them to develop an idea of personhood that is inclusive rather than exclusive — after all, if one's imagination readily grants full human rights to future AI programs, robots, dolphins, and extraterrestrial aliens, mere color and gender can't seem very important any more.

====Religion====
Agnostic. Atheist. Non-observant Jewish. Neo-pagan. Very commonly, three or more of these are combined in the same person. Conventional faith-holding Christianity is rare though not unknown. (I've noticed a disproportionate number of Mormon hackers, but I have an admittedly small sample. [[User:Crazyeddie|Crazyeddie]])

Even hackers who identify with a religious affiliation tend to be relaxed about it, hostile to organized religion in general and all forms of religious bigotry in particular. Many enjoy ‘parody’ religions such as [[Discordianism]] and the [[Church of the SubGenius]].

Also, many hackers are influenced to varying degrees by [[Zen]] Buddhism or (less commonly) Taoism, and blend them easily with their ‘native’ religions.

There is a definite strain of mystical, almost Gnostic sensibility that shows up even among those hackers not actively involved with neo-paganism, Discordianism, or Zen. Hacker folklore that pays homage to ‘[[wizards]]’ and speaks of [[incantation]]s and demons has too much psychological truthfulness about it to be entirely a joke.

====Ceremonial Chemicals====
Most hackers don't smoke tobacco, and use alcohol in moderation if at all. However, there has been something of a trend towards exotic beers since about 1995, especially among younger Linux hackers apparently influenced by Linus Torvalds's fondness for Guinness.

Limited use of non-addictive psychedelic drugs, such as cannabis, LSD, psilocybin, nitrous oxide, etc., used to be relatively common and is still regarded with more tolerance than in the mainstream culture. Use of ‘downers’ and opiates, on the other hand, appears to be particularly rare; hackers seem in general to dislike drugs that make them stupid. But [[on the gripping hand]], many hackers regularly wire up on caffeine and/or sugar for all-night hacking runs.

====Communication Style====
See the discussions of speech and writing styles near the beginning of this [[Jargon File|File]]. ''(Will provide links later, this hasn't been incorporated yet. [[User:Crazyeddie|Crazyeddie]]'' 15:53, Jul 24, 2004 (EDT)) Though hackers often have poor person-to-person communication skills, they are as a rule quite sensitive to nuances of language and very precise in their use of it. They are often better at writing than at speaking.

====Geographical Distribution====
In the United States, hackerdom revolves on a Bay Area-to-Boston axis; about half of the hard core seems to live within a hundred miles of Cambridge (Massachusetts) or Berkeley (California), although there are significant contingents in Los Angeles, in the Pacific Northwest, and around Washington DC. Hackers tend to cluster around large cities, especially ‘university towns’ such as the Raleigh-Durham area in North Carolina or Princeton, New Jersey (this may simply reflect the fact that many are students or ex-students living near their alma maters).

With the rise of the Internet, hackerdom has gone global, and more decentralised.

====Sexual Habits====
Hackerdom easily tolerates a much wider range of sexual and lifestyle variation than the mainstream culture. It includes a relatively large gay and bisexual contingent. Hackers are somewhat more likely to live in polygynous or polyandrous relationships, practice open marriage, or live in communes or group houses. In this, as in general appearance, hackerdom semi-consciously maintains ‘counterculture’ values.

====Personality Characteristics====
The most obvious common ‘personality’ characteristics of hackers are high intelligence, consuming curiosity, and facility with intellectual abstractions. Also, most hackers are ‘[[neophile]]s’, stimulated by and appreciative of novelty (especially intellectual novelty). Most are also relatively individualistic and anti-conformist.

Although high general intelligence is common among hackers, it is not the sine qua non one might expect. Another trait is probably even more important: the ability to mentally absorb, retain, and reference large amounts of ‘meaningless’ detail, trusting to later experience to give it context and meaning. A person of merely average analytical intelligence who has this trait can become an effective hacker, but a creative genius who lacks it will swiftly find himself outdistanced by people who routinely upload the contents of thick reference manuals into their brains. [During the production of the first book version of this document, for example, I learned most of the rather complex typesetting language [[TeX]] over about four working days, mainly by inhaling [[Knuth]]'s 477-page manual. My editor's flabbergasted reaction to this genuinely surprised me, because years of associating with hackers have conditioned me to consider such performances routine and to be expected. —[[ESR]]]

Contrary to stereotype, hackers are not usually intellectually narrow; they tend to be interested in any subject that can provide mental stimulation, and can often discourse knowledgeably and even interestingly on any number of obscure subjects — if you can get them to talk at all, as opposed to, say, going back to their hacking.

It is noticeable (and contrary to many outsiders' expectations) that the better a hacker is at hacking, the more likely he or she is to have outside interests at which he or she is more than merely competent.

Hackers are ‘control freaks’ in a way that has nothing to do with the usual coercive or authoritarian connotations of the term. In the same way that children delight in making model trains go forward and back by moving a switch, hackers love making complicated things like computers do nifty stuff for them. But it has to be their nifty stuff. They don't like tedium, nondeterminism, or most of the fussy, boring, ill-defined little tasks that go with maintaining a normal existence. Accordingly, they tend to be careful and orderly in their intellectual lives and chaotic elsewhere. Their code will be beautiful, even if their desks are buried in 3 feet of crap.

Hackers are generally only very weakly motivated by conventional rewards such as social approval or money. They tend to be attracted by challenges and excited by interesting toys, and to judge the interest of work or other activities in terms of the challenges offered and the toys they get to play with.

In terms of Myers-Briggs and equivalent psychometric systems, hackerdom appears to concentrate the relatively rare INTJ and INTP types; that is, introverted, intuitive, and thinker types (as opposed to the extroverted-sensate personalities that predominate in the mainstream culture). ENT[JP] types are also concentrated among hackers but are in a minority.

====Weaknesses of the Hacker Personality====
Hackers have relatively little ability to identify emotionally with other people. This may be because hackers generally aren't much like ‘other people’. Unsurprisingly, hackers also tend towards self-absorption, intellectual arrogance, and impatience with people and tasks perceived to be wasting their time.

As cynical as hackers sometimes wax about the amount of idiocy in the world, they tend by reflex to assume that everyone is as rational, ‘cool’, and imaginative as they consider themselves. This bias often contributes to weakness in communication skills. Hackers tend to be especially poor at confrontation and negotiation.

Another weakness of the hacker personality is a perverse tendancy to attack all problems from the most technically complicated angle, just because it may mean more interesting problems to solve, or cooler toys to play with. Hackers sometimes have trouble [[grok]]king that the bubble gum and paperclip hardware fix is actually the way to go, and that they really don't need to convince the client to buy that shiny new tool they've had your eye on for two months.

Because of their passionate embrace of (what they consider to be) the [[Right Thing]], hackers can be unfortunately intolerant and bigoted on technical issues, in marked contrast to their general spirit of camaraderie and tolerance of alternative viewpoints otherwise. Old-time [[ITS]] partisans look down on the ever-growing hordes of Unix and Linux hackers; Unix aficionados despise [[VMS]] and [[Windows]]; and hackers who are used to conventional [[cli|command-line user interfaces]] loudly loathe mouse-and-menu based systems such as the Macintosh. Hackers who don't indulge in [[Usenet]] consider it a huge waste of time and bandwidth; fans of old adventure games such as [[ADVENT]] and [[Zork]] consider [[MUD]]s to be glorified chat systems devoid of atmosphere or interesting puzzles; hackers who are willing to devote endless hours to Usenet or MUDs consider [[IRC]] to be a real waste of time; IRCies think MUDs might be okay if there weren't all those silly puzzles in the way. And, of course, there are the perennial [[holy wars]] — [[EMACS]] vs. [[vi]], [[big-endian]] vs. [[little-endian]], [[RISC]] vs. [[CISC]], etc., etc., etc. As in society at large, the intensity and duration of these debates is usually inversely proportional to the number of objective, factual arguments available to buttress any position.

As a result of all the above traits, many hackers have difficulty maintaining stable relationships. At worst, they can produce the classic [[geek]]: withdrawn, relationally incompetent, sexually frustrated, and desperately unhappy when not submerged in his or her craft. Fortunately, this extreme is far less common than mainstream folklore paints it — but almost all hackers will recognize something of themselves in the unflattering paragraphs above.

Hackers are often monumentally disorganized and sloppy about dealing with the physical world. Bills don't get paid on time, clutter piles up to incredible heights in homes and offices, and minor maintenance tasks get deferred indefinitely.

1994-95's fad behavioral disease was a syndrome called Attention Deficit Disorder (ADD), supposedly characterized by (among other things) a combination of short attention span with an ability to ‘hyperfocus’ imaginatively on interesting tasks. In 1998-1999 another syndrome that is said to overlap with many hacker traits entered popular awareness: Asperger's syndrome (AS). This disorder is also sometimes called ‘high-function autism’, though researchers are divided on whether AS is in fact a mild form of autism or a distinct syndrome with a different etiology. AS patients exhibit mild to severe deficits in interpreting facial and body-language cues and in modeling or empathizing with others' emotions. Though some AS patients exhibit mild retardation, others compensate for their deficits with high intelligence and analytical ability, and frequently seek out technical fields where problem-solving abilities are at a premium and people skills are relatively unimportant. Both syndromes are thought to relate to abnormalities in neurotransmitter chemistry, especially the brain's processing of serotonin.

Many hackers have noticed that mainstream culture has shown a tendency to pathologize and medicalize normal variations in personality, especially those variations that make life more complicated for authority figures and conformists. Thus, hackers aware of the issue tend to be among those questioning whether ADD and AS actually exist; and if so whether they are really ‘diseases’ rather than extremes of a normal genetic variation like having freckles or being able to taste DPT. In either case, they have a sneaking tendency to wonder if these syndromes are over-diagnosed and over-treated. After all, people in authority will always be inconvenienced by schoolchildren or workers or citizens who are prickly, intelligent individualists — thus, any social system that depends on authority relationships will tend to helpfully ostracize and therapize and drug such ‘abnormal’ people until they are properly docile and stupid and ‘well-socialized’.

So hackers tend to believe they have good reason for skepticism about clinical explanations of the hacker personality. That being said, most would also concede that some hacker traits coincide with indicators for non-hyperactive ADD and AS — the status of caffeine as a hacker beverage of choice may be connected to the fact that it bonds to the same neural receptors as Ritalin, the drug most commonly prescribed for ADD. It is probably true that boosters of both would find a rather higher rate of clinical ADD among hackers than the supposedly mainstream-normal 3-5% (AS is rarer at 0.4-0.5%).

====Miscellaneous====
Hackers are more likely to have cats than dogs (in fact, it is widely [[grok]]ked that cats have the hacker nature). Many drive incredibly decrepit heaps and forget to wash them; richer ones drive spiffy Porsches and RX-7s and then forget to have them washed. Almost all hackers have terribly bad handwriting, and often fall into the habit of block-printing everything like junior draftsmen.

==Famous Hackers==
*[[RMS|Richard M Stallman]]
*[[Linus Torvalds]]
*[[ESR|Eric S Raymond (ESR)]]

{{Jargon File/Attribution}}

Hack

2005-02-14T06:49:17Z

Frob23: Changed text attribution to template.

A '''hack''' is usually used to describe any clever bit of coding. It may be used in a negative sense to mean an overly clever or insufficiently refined bit of coding as well (e.g.: this is a hack; I'll fix it later). More commonly in the mass media, a 'hack' is used to describe a means of breaking into a system. The same grouping of ultimately contradictory meanings applies to 'hacker'. And, as a [[black hat hacker]] is more usefully referred to as a '[[crack]]er', so the malicious hack is a crack.

===Jargon File Definitions===
Some more definitions from the [[Jargon File]].

#n. Originally, a quick job that produces what is needed, but not well.
#n. An incredibly good, and perhaps very time-consuming, piece of work that produces exactly what is needed.
#vt. To bear emotionally or physically. “I can't hack this heat!”
#vt. To work on something (typically a program). In an immediate sense: “What are you doing?” “I'm hacking [[TECO]].” In a general (time-extended) sense: “What do you do around here?” “I hack TECO.” More generally, “I hack [[foo]]” is roughly equivalent to “foo is my major interest (or project)”. “I hack solid-state physics.” See [[Hacking X for Y]].
#vt. To pull a prank on. See sense 2 and [[hacker]] (sense 5).
#vi. To interact with a computer in a playful and exploratory rather than goal-directed way. “Whatcha up to?” “Oh, just hacking.”
#n. Short for [[hacker]].
#See [[nethack]].
#[MIT] v. To explore the basements, roof ledges, and steam tunnels of a large, institutional building, to the dismay of Physical Plant workers and (since this is usually performed at educational institutions) the Campus Police. This activity has been found to be eerily similar to playing adventure games such as Dungeons and Dragons and [[Zork]]. See also [[vadding]].

Constructions on this term abound. They include happy hacking (a farewell), how's hacking? (a friendly greeting among hackers) and hack, hack (a fairly content-free but friendly comment, often used as a temporary farewell). For more on this totipotent term see The Meaning of Hack. See also [[neat hack]], [[real hack]].

===The Meaning of Hack===
From the [[Jargon File]]:

“The word hack doesn't really have 69 different meanings”, according to MIT hacker Phil Agre. “In fact, hack has only one meaning, an extremely subtle and profound one which defies articulation. Which connotation is implied by a given use of the word depends in similarly profound ways on the context. Similar remarks apply to a couple of other hacker words, most notably [[random]].”

Hacking might be characterized as ‘an appropriate application of ingenuity’. Whether the result is a quick-and-dirty patchwork job or a carefully crafted work of art, you have to admire the cleverness that went into it.

An important secondary meaning of hack is ‘a creative practical joke’. This kind of hack is easier to explain to non-hackers than the programming kind. Of course, some hacks have both natures; see the lexicon entries for [[pseudo]] and [[kgbvax]]. But here are some examples of pure practical jokes that illustrate the hacking spirit:

====The Rose Bowl Hack====
:In 1961, students from Caltech (California Institute of Technology, in Pasadena) hacked the Rose Bowl football game. One student posed as a reporter and ‘interviewed’ the director of the University of Washington card stunts (such stunts involve people in the stands who hold up colored cards to make pictures). The reporter learned exactly how the stunts were operated, and also that the director would be out to dinner later.

:While the director was eating, the students (who called themselves the ‘Fiendish Fourteen’) picked a lock and stole a blank direction sheet for the card stunts. They then had a printer run off 2300 copies of the blank. The next day they picked the lock again and stole the master plans for the stunts — large sheets of graph paper colored in with the stunt pictures. Using these as a guide, they made new instructions for three of the stunts on the duplicated blanks. Finally, they broke in once more, replacing the stolen master plans and substituting the stack of diddled instruction sheets for the original set.

:The result was that three of the pictures were totally different. Instead of ‘WASHINGTON’, the word ‘CALTECH’ was flashed. Another stunt showed the word ‘HUSKIES’, the Washington nickname, but spelled it backwards. And what was supposed to have been a picture of a husky instead showed a beaver. (Both Caltech and MIT use the beaver — nature's engineer — as a mascot.)

:After the game, the Washington faculty athletic representative said: “Some thought it ingenious; others were indignant.” The Washington student body president remarked: “No hard feelings, but at the time it was unbelievable. We were amazed.”

This is now considered a classic hack, particularly because revising the direction sheets constituted a form of programming.

Here is another classic hack:

====Harvard-Yale Hack====
:On November 20, 1982, MIT hacked the Harvard-Yale football game. Just after Harvard's second touchdown against Yale, in the first quarter, a small black ball popped up out of the ground at the 40-yard line, and grew bigger, and bigger, and bigger. The letters ‘MIT’ appeared all over the ball. As the players and officials stood around gawking, the ball grew to six feet in diameter and then burst with a bang and a cloud of white smoke.

:The Boston Globe later reported: “If you want to know the truth, MIT won The Game.”

:The prank had taken weeks of careful planning by members of MIT's Delta Kappa Epsilon fraternity. The device consisted of a weather balloon, a hydraulic ram powered by Freon gas to lift it out of the ground, and a vacuum-cleaner motor to inflate it. They made eight separate expeditions to Harvard Stadium between 1 and 5 AM, locating an unused 110-volt circuit in the stadium and running buried wires from the stadium circuit to the 40-yard line, where they buried the balloon device. When the time came to activate the device, two fraternity members had merely to flip a circuit breaker and push a plug into an outlet.

:This stunt had all the earmarks of a perfect hack: surprise, publicity, the ingenious use of technology, safety, and harmlessness. The use of manual control allowed the prank to be timed so as not to disrupt the game (it was set off between plays, so the outcome of the game would not be unduly affected). The perpetrators had even thoughtfully attached a note to the balloon explaining that the device was not dangerous and contained no explosives.

:Harvard president Derek Bok commented: “They have an awful lot of clever people down there at MIT, and they did it again.” President Paul E. Gray of MIT said: “There is absolutely no truth to the rumor that I had anything to do with it, but I wish there were.”

The hacks above are verifiable history; they can be proved to have happened. Many other classic-hack stories from MIT and elsewhere, though retold as history, have the characteristics of what Jan Brunvand has called ‘urban folklore’ (see [[FOAF]]). Perhaps the best known of these is the legend of the infamous trolley-car hack, an alleged incident in which engineering students are said to have welded a trolley car to its tracks with thermite. Numerous versions of this have been recorded from the 1940s to the present, most set at MIT but at least one very detailed version set at CMU.

Brian Leibowitz has researched MIT hacks both real and mythical extensively; the interested reader is referred to his delightful pictorial compendium The Journal of the Institute for Hacks, Tomfoolery, and Pranks (MIT Museum, 1990; ISBN 0-917027-03-5). The Institute has a World Wide Web page at http://hacks.mit.edu/Hacks/Gallery.html. There is a sequel entitled Is This The Way To Baker House?. The Caltech Alumni Association has published two similar books titled Legends of Caltech and More Legends of Caltech.

Here is a story about one of the classic computer hacks:

====Robin Hood and Friar Tuck====
This particular hack is an example of [[grey hat]] hacking.

:Back in the mid-1970s, several of the system support staff at [[Motorola]] discovered a relatively simple way to crack system security on the [[Xerox]] CP-V [[timesharing]] system. Through a simple programming strategy, it was possible for a user program to trick the system into running a portion of the program in ‘master mode’ (supervisor state), in which memory protection does not apply. The program could then poke a large value into its ‘privilege level’ byte (normally write-protected) and could then proceed to bypass all levels of security within the file-management system, patch the system monitor, and do numerous other interesting things. In short, the barn door was wide open.

:Motorola quite properly reported this problem to Xerox via an official ‘level 1 SIDR’ (a bug report with an intended urgency of ‘needs to be fixed yesterday’). Because the text of each SIDR was entered into a database that could be viewed by quite a number of people, Motorola followed the approved procedure: they simply reported the problem as ‘Security SIDR’, and attached all of the necessary documentation, ways-to-reproduce, etc.

:The CP-V people at Xerox sat on their thumbs; they either didn't realize the severity of the problem, or didn't assign the necessary operating-system-staff resources to develop and distribute an official patch.

:Months passed. The Motorola guys pestered their Xerox field-support rep, to no avail. Finally they decided to take direct action, to demonstrate to Xerox management just how easily the system could be cracked and just how thoroughly the security safeguards could be subverted.

:They dug around in the operating-system listings and devised a thoroughly devilish set of patches. These patches were then incorporated into a pair of programs called ‘Robin Hood’ and ‘Friar Tuck’. Robin Hood and Friar Tuck were designed to run as ‘ghost jobs’ ([[daemons]], in Unix terminology); they would use the existing loophole to subvert system security, install the necessary patches, and then keep an eye on one another's statuses in order to keep the system operator (in effect, the superuser) from aborting them.

:One fine day, the system operator on the main CP-V software development system in El Segundo was surprised by a number of unusual phenomena. These included the following:

:*[[Tape drive]]s would rewind and dismount their tapes in the middle of a job.
:*Disk drives would seek back and forth so rapidly that they would attempt to walk across the floor (see [[walking drives]]).
:*The [[card-punch]] output device would occasionally start up of itself and punch a ‘[[lace card]]’ (card with all positions punched). These would usually jam in the punch.
:*The console would print snide and insulting messages from Robin Hood to Friar Tuck, or vice versa.
:*The Xerox card reader had two output stackers; it could be instructed to stack into A, stack into B, or stack into A (unless a card was unreadable, in which case the bad card was placed into stacker B). One of the patches installed by the ghosts added some code to the card-reader driver... after reading a card, it would flip over to the opposite stacker. As a result, card decks would divide themselves in half when they were read, leaving the operator to recollate them manually.

:Naturally, the operator called in the operating-system developers. They found the bandit ghost jobs running, and [[kill]]ed them... and were once again surprised. When Robin Hood was [[gun]]ned, the following sequence of events took place:

<tt>!X id1

id1: Friar Tuck... I am under attack! Pray save me!
id1: Off (aborted)

id2: Fear not, friend Robin! I shall rout the Sheriff
of Nottingham's men!

id1: Thank you, my good fellow!</tt>

:Each ghost-job would detect the fact that the other had been killed, and would start a new copy of the recently slain program within a few milliseconds. The only way to kill both ghosts was to kill them simultaneously (very difficult) or to deliberately crash the system.

:Finally, the system programmers did the latter — only to find that the bandits appeared once again when the system rebooted! It turned out that these two programs had patched the boot-time OS image (the kernel file, in Unix terms) and had added themselves to the list of programs that were to be started at boot time (this is similar to the way Windows viruses propagate).

:The Robin Hood and Friar Tuck ghosts were finally eradicated when the system staff rebooted the system from a clean boot-tape and reinstalled the monitor. Not long thereafter, Xerox released a patch for this problem.

:It is alleged that Xerox filed a complaint with Motorola's management about the merry-prankster actions of the two employees in question. It is not recorded that any serious disciplinary action was taken against either of them.

{{Jargon File/Attribution}}

====Transmission of IP Datagrams on Avian Carriers====
Finally, here is a wonderful hack story for the new millennium:

1990's addition to the hallowed tradition of April Fool RFCs was [[RFC]] 1149, A Standard for the Transmission of [[IP]] [[Datagram]]s on Avian Carriers. This sketched a method for transmitting IP [[packet]]s via carrier pigeons.

Eleven years later, on 28 April 2001, the Bergen [[LUG|Linux User's Group]] successfully demonstrated CPIP (Carrier Pigeon IP) between two Linux machines running on opposite sides of a small mountain in Bergen, Norway. Their network stack used printers to [[hex]]-dump packets onto paper, pigeons to transport the paper, and [[OCR]] software to read the dumps at the other end and feed them to the receiving machine's network layer.

Here is the actual log of the ping command they successfully executed. Note the exceptional packet times.

<tt>Script started on Sat Apr 28 11:24:09 2001
vegard@gyversalen:~$ /sbin/ifconfig tun0
tun0 Link encap:Point-to-Point Protocol
inet addr:10.0.3.2 P-t-P:10.0.3.1 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:150 Metric:1
RX packets:1 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0
RX bytes:88 (88.0 b) TX bytes:168 (168.0 b)

vegard@gyversalen:~$ ping -i 450 10.0.3.1
PING 10.0.3.1 (10.0.3.1): 56 data bytes
64 bytes from 10.0.3.1: icmp_seq=0 ttl=255 time=6165731.1 ms
64 bytes from 10.0.3.1: icmp_seq=4 ttl=255 time=3211900.8 ms
64 bytes from 10.0.3.1: icmp_seq=2 ttl=255 time=5124922.8 ms
64 bytes from 10.0.3.1: icmp_seq=1 ttl=255 time=6388671.9 ms

— 10.0.3.1 ping statistics —
9 packets transmitted, 4 packets received, 55% packet loss
round-trip min/avg/max = 3211900.8/5222806.6/6388671.9 ms
vegard@gyversalen:~$ exit

Script done on Sat Apr 28 14:14:28 2001</tt>

A web page documenting the event, with pictures, is at http://www.blug.linux.no/rfc1149/ . In the finest Internet tradition, all software involved was [[Open Source]]; the custom parts are available for download from the site.

While all acknowledged the magnitude of this achievement, some debate ensued over whether BLUG's implementation was properly conformant to the RFC. It seems they had not used the duct tape specified in 1149 to attach messages to pigeon legs, but instead employed other methods less objectionable to the pigeons. The debate was properly resolved when it was pointed out that the duct-tape specification was not prefixed by a MUST, and was thus a recommendation rather than a requirement.

The perpetrators finished their preliminary writeup in this wise: “Now, we're waiting for someone to write other implementations, so that we can do interoperability tests, and maybe we finally can get the RFC into the standards track... ”.

The logical next step should be an implementation of RFC2549.

==See also==
*[[Programming]]

==External Links==
* http://www.spril.com/StealthForceBeta/ ''The stories of a team of reality hackers (the staute of limitations has passed!)''

Front end

2005-02-14T06:36:34Z

Frob23: Changed text attribution to template.

The term '''front end''' can mean:

#An intermediary computer that does set-up and filtering for another (usually more powerful but less friendly) machine (a [[back end]]).
#What you're talking to when you have a conversation with someone who is making replies without paying attention. “Look at the dancing elephants!” “Uh-huh.” “Do you know what I just said?” “Sorry, you were talking to the front end.”
#Software that provides an interface to another program ‘behind’ it, which may not be as user-friendly. Probably from analogy with hardware front-ends (see sense 1) that interfaced with [[mainframe]]s.

==See also==
*[[back end]]
*[[engine]]
*[[GUI]]

{{Jargon File/Attribution}}

Talk:Set up a Trust 235a Speedlink Webmodem

2005-01-31T08:37:24Z

Frob23:

I don't know what you (hvdivries) mean in steps 7 and 8. Want to clarify?

--[[User:Lamb|Lamb]] 20:16, Dec 15, 2004 (EST)

<hr>

when you have installed cxacru(tar.gz for2.6.xkernels) you have to open file/etc/cxacru (root,with kwrite) and change `protocol 1`in`2` then change vpi andvci according your modem values. then do the same with file:/ppp/options remove options and replace it for new options file like........noipdefault
noauth
persist
lcp-max-configure 50
usepeerdns
name any
user "login name"
defaultroute
plugin /usr/lib/pppd/2.4.1/pppoatm.so 8.48..........(8.48 are my modem vpi and vci values)

<hr>

So if I get this straight you mean:

When you have installed cxacru you have to open file /etc/cxacru (as root) and change `protocol 1` to `protocol 2` then edit the values of vpi and vci according to your modem.

Then remove /ppp/options and replace it with a new options file somewhat like this:

noipdefault 
noauth 
persist 
lcp-max-configure 50 
usepeerdns 
name any 
user "YOUR LOGIN NAME HERE" 
defaultroute 
plugin /usr/lib/pppd/2.4.1/pppoatm.so 8.48 (I use 8.48 because thats what my modem's vpi and vci values are.)

Eh? [[User:Lamb|Lamb]] 18:31, Dec 28, 2004 (EST)

correct

----

Is there any reason this is PPoE instead of PPPoE ??

--[[User:Frob23|Frob23]] 03:37, Jan 31, 2005 (EST)

Ed

2005-01-25T17:46:59Z

Frob23: /* Usage */ minor edits, typo and readability.

'''ed''' is one of the most noted original editors on Unix and Unix-like systems written by Ken Thompson. Ed is a line editor unlike the newer screen oriented editors [[vi]] or [[emacs]].

It is noted for its extreme terseness, and has been the subject to Usenet humor, such as the post below.

It is the default command-line based editor in the [[Plan 9]] [[operating system]], apart from [[acme]] and [[sam]].

==To use ed==
$ed

a ''(To add or append text)''
Type something here.
. ''(Signals end of input. Will not show up in file)''
w foo ''(Write to file named foo)''
q ''(To quit ed)''
$ cat foo
Type something here.
$

It is important to remember that ed is a line editing tool. This means that it deals with the text of a file one line at a time or as groups of lines. When this is understood the basic usage of ed becomes fairly simple. The file is loaded into a buffer which is independent from the copy on the disk until you write it out. ed is also a modal editor. This means it has separate command and input modes much like [[vi]].

===Basic Commands===

a -- append a new line after the current line.
i -- insert a new line above the current line.
d -- delete the current line.
p -- print the current line.
n -- print the current line preceded by it's line number.
u -- undo the last command (a second u undoes the undo).
w -- write the buffer to disk.
q -- quit.

h -- expand on last error ?.

Note on the '?' for an error. If you want to know what the error dealt with you can enter the command 'h' and it will give you a "slightly" better error message.

===Usage===

If you refer to the first example given you see a clear guide of usage. When you first enter ed you are in command mode. If you have loaded a pre-existing file, ed will print the number of bytes loaded and wait for your command. It automatically starts you with your current line equal to the last line of the file so you can easily start appending text.

Almost all of ed's commands can take a line number or a range of lines as an option. For example, to print the first 10 lines of a file you would enter:
1,10p

To delete the 5th line from a file all you need to do is enter:
5d

Movement is also very easy. You just enter the line number you wish to go to. To get the the start of a file after you load it, simply enter:
1

There are some other little shortcuts to know about when dealing with lines. A '$' (dollar sign) refers to the last line of the file. A '.' (period) refers to the current line. This is very useful because you can use these before any command to give a range for it to work on. To delete every line from the current line to the end of the file, you would enter:
.,$d

Sometimes you will enter a command and not see your expected result. There is no error (?), just complete silence. In almost every instance, that this happens, you are in input mode and not command mode. To exit input mode you need to enter a '.' on a line by itself. What follows is an example editing session. The comments (everything after the ;) are not supposed to be typed in.

$ed
5432 ''; The number of bytes loaded.''
. ''; This prints the current line.''
What a funny line to end a file with.
.= ''; Print the current line number.''
132
130,$p ''; Print the last three lines.''
This is weird.
A fake little file.
What a funny line to end a file with.
d ''; delete the current line''
a ''; add new text.''
This is a much better final line.
p
''; ??? Why didn't this show our new line?''
''; Because we are still in input mode.''
. ''; exit input mode''
p ''; print the current line''
p ''; it is our 'p' we accidentally added''
d ''; delete the current line''
p ''; print our new current line''
This is a much better final line.
w ''; that is good so save the file''
5428 ''; the number of bytes saved''
q ''; quit''

Knowing these simple commands and understanding how they effect the file can often save you if you are unable to use a different editor. ed is actually a very nice little editor with some built-in power which might surprise you. The man page is highly recommended reading and it never hurt anyone to spend 15-20 minutes experimenting with this editor. [http://www.freebsd.org/cgi/man.cgi?query=ed&apropos=0&sektion=0&manpath=Red+Hat+Linux%2Fi386+9&format=html ed man page]

==Jargon File on ed==
“ed is the standard text editor.” Line taken from the original Unix manual page on ed, an ancient line-oriented editor that is by now used only by a few [[Real Programmer]]s, and even then only for [[batch]] operations. The original line is sometimes uttered near the beginning of an [[emacs]] vs. [[vi]] [[holy war]] on [[Usenet]], with the (vain) hope to quench the discussion before it really takes off. Often followed by a standard text describing the many virtues of ed (such as the small memory footprint on a Timex Sinclair, and the consistent (because nearly non-existent) user interface).

{{Jargon File/Attribution}}

== Usenet humor about ed==



----- Begin included message -----
From: patl@athena.mit.edu (Patrick J. LoPresti)
Message-ID: <1991Jul11.031731.9260@athena.mit.edu>
Sender: news@athena.mit.edu (News system)
Subject: The True Path (long)
Date: 11 Jul 91 03:17:31 GMT
Newsgroups: alt.religion.emacs,alt.slack
Organization: Massachusetts Institute of Technology
Lines: 95

When I log into my [[Xenix]] system with my 110 baud [[teletype]], both [[vi]]
*and* [[Emacs]] are just too damn slow. They print useless messages like,
'C-h for help' and '"[[foo]]" File is read only'. So I use the editor
that doesn't waste my VALUABLE time.

Ed, man! ![[man]] ed

ED(1) UNIX Programmer's Manual ED(1)

NAME
ed - text editor

SYNOPSIS
ed [ - ] [ -x ] [ name ]
DESCRIPTION
Ed is the standard text editor.
-----

Computer Scientists love ed, not just because it comes first
alphabetically, but because it's the standard. Everyone else loves ed
because it's ED!

"Ed is the standard text editor."

And ed doesn't waste space on my Timex Sinclair. Just look:

-rwxr-xr-x 1 root 24 Oct 29 1929 /bin/ed
-rwxr-xr-t 4 root 1310720 Jan 1 1970 /usr/ucb/vi
-rwxr-xr-x 1 root 5.89824e37 Oct 22 1990 /usr/bin/emacs

Of course, on the system *I* administrate, vi is symlinked to ed.
Emacs has been replaced by a shell script which 1) Generates a syslog
message at level LOG_EMERG; 2) reduces the user's disk quota by 100K;
and 3) RUNS ED!!!!!!

"Ed is the standard text editor."

Let's look at a typical novice's session with the mighty ed:

golem> ed

?
help
?
?
?
quit
?
exit
?
bye
?
hello?
?
[[eat flaming death]]
?
^C
?
^C
?
^D
?

---
Note the consistent user interface and error reportage. Ed is
generous enough to flag errors, yet prudent enough not to overwhelm
the novice with verbosity.

"Ed is the standard text editor."

Ed, the greatest [[WYGIWYG]] editor of all.

ED IS THE TRUE PATH TO NIRVANA! ED HAS BEEN THE CHOICE OF
EDUCATED AND IGNORANT ALIKE FOR CENTURIES! ED WILL NOT CORRUPT YOUR
PRECIOUS BODILY FLUIDS!! ED IS THE STANDARD TEXT EDITOR! ED MAKES THE SUN
SHINE AND THE BIRDS SING AND THE GRASS GREEN!!

When I use an editor, I don't want eight extra KILOBYTES of worthless
help screens and cursor positioning code! I just want an EDitor!!
Not a "viitor". Not a "emacsitor". Those aren't even WORDS!!!! ED!
ED! ED IS THE STANDARD!!!

TEXT EDITOR.

When IBM, in its ever-present omnipotence, needed to base their
"edlin" on a UNIX standard, did they mimic vi? No. Emacs? Surely
you jest. They chose the most karmic editor of all. The standard.

Ed is for those who can *remember* what they are working on. If you
are an idiot, you should use Emacs. If you are an Emacs, you should
not be vi. If you use ED, you are on THE PATH TO REDEMPTION. THE
SO-CALLED "VISUAL" EDITORS HAVE BEEN PLACED HERE BY ED TO
TEMPT THE FAITHLESS. DO NOT GIVE IN!!! THE MIGHTY ED HAS SPOKEN!!!

--
Miquel van Smoorenburg | Our vision is to speed up time,
miquels@cistron.nl | eventually eliminating it.

----- End included message -----

E-mail

2005-01-25T17:40:27Z

Frob23: Changed text attribution to template.

'''E-mail''' allows users to send and recieve "electronic mail" over the [[internet]]. It is cheap and efficient, being almost instantly recieved if your server is quick enough.

Users can recieve e-mail through an [[email client]] (also known as an MUA - mail user agent) provided that they have a [[POP3]] or [[IMAP]] email account. Anybody can send e-mail through [[SMTP]] but it is good practice and indeed good manners to do this attached to your own e-mail address and not to freeload with a nonexistant one or somebody else's.

Oddly enough, the word emailed is actually listed in Oxford's English Dictionary (before email became popular); it means “embossed (with a raised pattern) or perh. arranged in a net or open work”. A use from 1480 is given. The word is probably derived from French émaillé (enameled) and related to Old French emmailleüre (network). A French correspondent tells us that in modern French, ‘email’ is a hard enamel obtained by heating special paints in a furnace; an ‘emailleur’ (no final e) is a craftsman who makes email (he generally paints some objects (like, say, jewelry) and cooks them in a furnace).

There are numerous spelling variants of this word. In Internet traffic up to 1995, ‘email’ predominates, ‘e-mail’ runs a not-too-distant second, and ‘E-mail’ and ‘Email’ are a distant third and fourth.

==See also==
*[[End User Manual:Internet email]]
*[[snail-mail]]
*[[paper-net]]
*[[voice-net]]
*[[network address]]

{{Jargon File/Attribution}}

Emacs

2005-01-25T17:39:53Z

Frob23: Changed text attribution to template.

'''Emacs'''; ('''E'''diting '''MAC'''ro'''S''') The ne plus ultra of hacker [[editor]]s, a programmable text editor with an entire [[LISP]] system inside it. It was originally written by [[Richard Stallman]] in [[TECO]] under [[ITS]] at the [[MIT AI lab]]; AI Memo 554 described it as “an advanced, self-documenting, customizable, extensible real-time display editor”. It has since been reimplemented any number of times, by various hackers, and versions exist that run under most major [[operating system]]s. Perhaps the most widely used version, also written by Stallman and now called “[[GNU]] EMACS” or GNUMACS, runs principally under Unix. (Its close relative [[XEmacs]] is the second most popular version.) It includes facilities to run compilation subprocesses and send and receive [[email]] or news; many hackers, before the time of [[GUI]]s, spent up to 80% of their tube time inside it. Other variants include [[GOSMACS]], CCA EMACS, UniPress EMACS, Montgomery EMACS, [[jove]], epsilon, and MicroEMACS. (Though we use the original all-caps spelling here, it is nowadays very commonly ‘Emacs’.) Some EMACS versions running under window managers iconify as an overflowing kitchen sink, perhaps to suggest the one feature the editor does not (yet) include. Indeed, some hackers find EMACS too [[heavyweight]] and [[baroque]] for their taste, and expand the name as "'''E'''scape '''M'''eta '''A'''lt '''C'''ontrol '''S'''hift" to spoof its heavy reliance on keystrokes decorated with [[bucky bit]]s. Other spoof expansions include "'''E'''ight '''M'''egabytes '''A'''nd '''C'''onstantly [[Swap]]ping" (from when that was a lot of [[core]]), ‘Eventually [[malloc]]()s All Computer Storage’, and ‘EMACS Makes A Computer Slow’ (see [[recursive acronym]]).

The latest stable release of GNU EMACS, 21.3, was released on March 24, 2003.

===Vi vs. Emacs===
Emacs vs [[vi]] is the subject of a [[holy war]], but this has largely been settled by the rise of [[WYSIWYG]] editors, which have tended to displace both options, and faster hardware, which renders the baroque nature of emacs irrelevant. The Emacs camp is sometimes jokingly referred to as the "Church of Emacs". In fact, as a gag, at his talks, [[RMS]] has been known to don a gown and halo and address his apostles:

:Finally, when Saint IGNUcius was asked if using <tt>vi</tt> in the Church of Emacs was a sin, he replied, "We of the Church of Emacs believe that use of <tt>vi</tt> is not a sin, but rather penance."


===Buckies===
The [[space-cadet keyboard]] was an inspiration for emacs. This is where all the C-''x'' (That's emacs notation for pressing the Control key while hitting the ''x'' key) and M-''x'' (same thing, only with the Alt key instead of the Control key) commands came from. These chorded keystrokes make use of "buckies", or special function keys like Control, Alt, and Shift. The name bucky comes from the early days of keyboards, before they standardized on [[ASCII]]. In those days, characters used 7 [[bit]]s, and bucky keys turned on extra bits, which were called [[bucky bits]], [[meta bits]], or high bits, to the top of the character's [[byte]]. This changed the value of the character's byte, and produced a different character.

The use of buckies means that an experienced emacs user has a wide range of commands available in just a few keystrokes, and doesn't have to take their hands off the main keyboard to use the arrow keys or the mouse. On the downside, there are a lot of commands to memorize (although you can usually muddle along with the arrow keys or the menu). Also, some key chords are hard to pull off. But at least emacs is better than the space-cadet keyboard. There are occasionally [[double bucky|double buckies]] (where you press Ctrl, Alt, and another key) but triple or even [[quadruple bucky|quadruple buckies]] are very rare. (In fact, quadruple buckies are impossible to do on present day keyboards. A triple bucky would require the use of the Shift key.)

===Features===
Emacs supports syntax highlighting, [[CVS]], [[diff]]/[[patch]] and many other features, which draw on Emacs' built-in LISP extensibility.

Around version 19 a fork of the GNU Emacs project resulted in an alternate version [[XEmacs]]. Both versions are now actively developed. The reasons for the fork are detailed on http://www.xemacs.org, but in short you could say that GNU Emacs is [[Free Software]] while XEmacs is more [[Open Source]] Software. XEmacs readily adopts changes from Emacs into it's code base, so XEmacs arguable has more features. In practice the editors a much alike, so most you read about Emacs should apply to XEmacs and vice versa.

[[ELSE]], the Emacs Language Sensitive Editor is an installable mode of the editor.

A primary attraction of Emacs is it's excellent syntax highlighting (called font-locking) and indentation support, as well as a lot of advanced editing tricks. Functions such as indent-function, hungry delete and other advanced tricks makes Emacs users incredible productive . The flip side of the coin is that this enormous functionality has to be mastered, which takes some time.

Emacs comes with an excellent tutorial and auto-generated documentation. To access the tutorial, press h while holding down the Control key, release the control key and press t.

==See also==
* [[Emacs keystrokes]]
* [[Emacs modes]]
* [[Keyboard shortcuts at a glance]]

==External links==
* [http://www.gnu.org/software/emacs/ Official Emacs homepage]
* [http://www.zipworld.com.au/~peterm/ ELSE]
*[http://www.emacswiki.org/ Wiki for Emacs]
*[http://www.dotfiles.com/index.php3?app_id=6 Free customised .emacs files]
*[http://www.xemacs.org/ Official XEmacs homepage]

{{Jargon File/Attribution}}

Ed

2005-01-25T17:37:47Z

Frob23: /* Jargon File on ed */ changed text attribution to template.

'''ed''' is one of the most noted original editors on Unix and Unix-like systems written by Ken Thompson. Ed is a line editor unlike the newer screen oriented editors [[vi]] or [[emacs]].

It is noted for its extreme terseness, and has been the subject to Usenet humor, such as the post below.

It is the default command-line based editor in the [[Plan 9]] [[operating system]], apart from [[acme]] and [[sam]].

==To use ed==
$ed

a ''(To add or append text)''
Type something here.
. ''(Signals end of input. Will not show up in file)''
w foo ''(Write to file named foo)''
q ''(To quit ed)''
$ cat foo
Type something here.
$

It is important to remember that ed is a line editing tool. This means that it deals with the text of a file one line at a time or as groups of lines. When this is understood the basic usage of ed becomes fairly simple. The file is loaded into a buffer which is independent from the copy on the disk until you write it out. ed is also a modal editor. This means it has separate command and input modes much like [[vi]].

===Basic Commands===

a -- append a new line after the current line.
i -- insert a new line above the current line.
d -- delete the current line.
p -- print the current line.
n -- print the current line preceded by it's line number.
u -- undo the last command (a second u undoes the undo).
w -- write the buffer to disk.
q -- quit.

h -- expand on last error ?.

Note on the '?' for an error. If you want to know what the error dealt with you can enter the command 'h' and it will give you a "slightly" better error message.

===Usage===

If you refer to the first example given you see a clear guide of usage. When you first enter ed you are in command mode. If you have loaded a pre-existing file, ed will print the number of bytes loaded and wait for your command. It automatically starts you with your current line equal to the last line of the file so you can easily start appending text.

Almost all of ed's commands can take a line number or a range of lines as an option. For example, to print the first 10 lines of a file you would enter:
1,10p

To delete the 5th line from a file all you need to do is enter:
5d

Movement is also very easy. You just enter the line number you wish to go to. To get the the start of a file after you load it, simple enter:
1

There are some other little shortcuts to know about when dealing with lines. A '$' (dollar sign) refers to the last line of the file. A '.' (period) refers to the current line. This is very useful because you can use these before any command to give a range for it to work on. To delete every line from the current line to the end of the file, you would enter:
.,$d

What happens frequently is you will enter a command and not see your expected result. There is no error (?) just complete silence. In almost every instance of this you are in input mode and not command mode. To exit input mode you need to enter a '.' on a line by itself. What follows is an example editing session. The comments (everything after the ;) are not supposed to be typed in.

$ed
5432 ''; The number of bytes loaded.''
. ''; This prints the current line.''
What a funny line to end a file with.
.= ''; Print the current line number.''
132
130,$p ''; Print the last three lines.''
This is weird.
A fake little file.
What a funny line to end a file with.
d ''; delete the current line''
a ''; add new text.''
This is a much better final line.
p
''; ??? Why didn't this show our new line?''
''; Because we are still in input mode.''
. ''; exit input mode''
p ''; print the current line''
p ''; it is our 'p' we accidentally added''
d ''; delete the current line''
p ''; print our new current line''
This is a much better final line.
w ''; that is good so save the file''
5428 ''; the number of bytes saved''
q ''; quit''

Knowing these simple commands and understanding how they effect the file can often save you if you are unable to use a different editor. ed is actually a very nice little editor with some built in power which might surprise you. The man page is highly recommended reading and it never hurt anyone to spend 15-20 minutes experimenting with this editor. [http://www.freebsd.org/cgi/man.cgi?query=ed&apropos=0&sektion=0&manpath=Red+Hat+Linux%2Fi386+9&format=html ed man page]

==Jargon File on ed==
“ed is the standard text editor.” Line taken from the original Unix manual page on ed, an ancient line-oriented editor that is by now used only by a few [[Real Programmer]]s, and even then only for [[batch]] operations. The original line is sometimes uttered near the beginning of an [[emacs]] vs. [[vi]] [[holy war]] on [[Usenet]], with the (vain) hope to quench the discussion before it really takes off. Often followed by a standard text describing the many virtues of ed (such as the small memory footprint on a Timex Sinclair, and the consistent (because nearly non-existent) user interface).

{{Jargon File/Attribution}}

== Usenet humor about ed==



----- Begin included message -----
From: patl@athena.mit.edu (Patrick J. LoPresti)
Message-ID: <1991Jul11.031731.9260@athena.mit.edu>
Sender: news@athena.mit.edu (News system)
Subject: The True Path (long)
Date: 11 Jul 91 03:17:31 GMT
Newsgroups: alt.religion.emacs,alt.slack
Organization: Massachusetts Institute of Technology
Lines: 95

When I log into my [[Xenix]] system with my 110 baud [[teletype]], both [[vi]]
*and* [[Emacs]] are just too damn slow. They print useless messages like,
'C-h for help' and '"[[foo]]" File is read only'. So I use the editor
that doesn't waste my VALUABLE time.

Ed, man! ![[man]] ed

ED(1) UNIX Programmer's Manual ED(1)

NAME
ed - text editor

SYNOPSIS
ed [ - ] [ -x ] [ name ]
DESCRIPTION
Ed is the standard text editor.
-----

Computer Scientists love ed, not just because it comes first
alphabetically, but because it's the standard. Everyone else loves ed
because it's ED!

"Ed is the standard text editor."

And ed doesn't waste space on my Timex Sinclair. Just look:

-rwxr-xr-x 1 root 24 Oct 29 1929 /bin/ed
-rwxr-xr-t 4 root 1310720 Jan 1 1970 /usr/ucb/vi
-rwxr-xr-x 1 root 5.89824e37 Oct 22 1990 /usr/bin/emacs

Of course, on the system *I* administrate, vi is symlinked to ed.
Emacs has been replaced by a shell script which 1) Generates a syslog
message at level LOG_EMERG; 2) reduces the user's disk quota by 100K;
and 3) RUNS ED!!!!!!

"Ed is the standard text editor."

Let's look at a typical novice's session with the mighty ed:

golem> ed

?
help
?
?
?
quit
?
exit
?
bye
?
hello?
?
[[eat flaming death]]
?
^C
?
^C
?
^D
?

---
Note the consistent user interface and error reportage. Ed is
generous enough to flag errors, yet prudent enough not to overwhelm
the novice with verbosity.

"Ed is the standard text editor."

Ed, the greatest [[WYGIWYG]] editor of all.

ED IS THE TRUE PATH TO NIRVANA! ED HAS BEEN THE CHOICE OF
EDUCATED AND IGNORANT ALIKE FOR CENTURIES! ED WILL NOT CORRUPT YOUR
PRECIOUS BODILY FLUIDS!! ED IS THE STANDARD TEXT EDITOR! ED MAKES THE SUN
SHINE AND THE BIRDS SING AND THE GRASS GREEN!!

When I use an editor, I don't want eight extra KILOBYTES of worthless
help screens and cursor positioning code! I just want an EDitor!!
Not a "viitor". Not a "emacsitor". Those aren't even WORDS!!!! ED!
ED! ED IS THE STANDARD!!!

TEXT EDITOR.

When IBM, in its ever-present omnipotence, needed to base their
"edlin" on a UNIX standard, did they mimic vi? No. Emacs? Surely
you jest. They chose the most karmic editor of all. The standard.

Ed is for those who can *remember* what they are working on. If you
are an idiot, you should use Emacs. If you are an Emacs, you should
not be vi. If you use ED, you are on THE PATH TO REDEMPTION. THE
SO-CALLED "VISUAL" EDITORS HAVE BEEN PLACED HERE BY ED TO
TEMPT THE FAITHLESS. DO NOT GIVE IN!!! THE MIGHTY ED HAS SPOKEN!!!

--
Miquel van Smoorenburg | Our vision is to speed up time,
miquels@cistron.nl | eventually eliminating it.

----- End included message -----

Dot file

2005-01-25T03:54:10Z

Frob23: Changed text attribution to template.

A '''dot file''' is a file that is not visible by default to normal directory-browsing tools (on Unix, files named with a leading dot are, by convention, not normally presented in directory listings). They are, in a sense, "hidden", to use the terminology of Windows. 

For this reason, many programs define one or more dot files in which startup or configuration information may be optionally recorded; either a program can create a dotfile with configuration, or a user can customize the program's behavior by creating the appropriate file in the current or home directory. Therefore, dot files tend to creep with every nontrivial application program defining at least one, a user's home directory can be filled with scores of dot files, of course without the user's really being aware of it.

In the shell, a * is not meant the same as in a [[regular expression]], for one, because it would include the current directory, "." and parent directory "files" (See [[glob]]). As such, ''never'' use <tt>.*</tt> to affect all dot files for this reason! Instead, use <tt>.[A-Za-z0-9]*</tt> In [[bash]], you can also change the [[dotglob]] variable to let * affect dot files. This will not affect "." and "..".

===See also===
*[[profile]]
*[[rc file]]

{{Jargon File/Attribution}}

Deprecated

2005-01-25T03:50:33Z

Frob23: Changed text attribution to template.

When a program or [[feature]] is considered obsolescent and in the process of being phased out, usually in favor of a specified replacement, it is said to be '''deprecated'''. Deprecated features can, unfortunately, linger on for many years. This term appears with distressing frequency in standards documents when the committees writing the documents realize that large amounts of extant (and presumably happily working) code depend on the feature(s) that have passed out of favor. See also [[dusty deck]].

Also, sometimes, the use of an entire software package (or, at the other extreme, maybe just a few [[library]] calls) might be deprecated in favor of more modern and current replacements.

[Usage note: don't confuse this word with ‘depreciated’, or the verb form ‘deprecate’ with ‘depreciate’. They are different words; see any dictionary for discussion.]

{{Jargon File/Attribution}}

Dd

2005-01-25T03:49:34Z

Frob23: Changed text attribution to template.

The '''dd''' command copies data from one place to another. Sometimes [[cat]] can do the same thing (with [[redirection]]), but dd has options to translate data, selectively copy only part of a data stream, and buffer its reads and writes.

Dd can [[Making_an_ISO_from_CDROM|copy a CD to an ISO file]], copy one partition to another, or restore an image file to a disk. Using the <tt>seek</tt> and <tt>count</tt> options, an individual sector of a disk can be extracted without having to wait for the entire rest of the disk to be read.

Also see the very useful tool [[dd_rescue]], which you can use to recover media with errors on it.

Since dd can be easily used to [[munge]] a hard drive, it (hopefully) is a [[superuser]]-only tool.

==Examples==

===Creating a hard drive backup image===

The main options to be concerned about are if= (input file) and of= (output file). By default, dd reads from [[stdin]] and writes to [[stdout]]. Here is an example of a use for dd:

# dd if=/dev/hda | gzip > /mnt/hdb1/system_drive_backup.img.gz

Here dd is making an image of the first harddrive, and piping it through the [[gzip]] compression program. The compressed image is then placed in a file on a seperate drive. To reverse the process:

# gzip -dc /mnt/hdb1/system_drive_backup.img.gz | dd of=/dev/hda

Here, gzip is decompressing (the -d switch) the file, sending the results to stdout (the -c switch), which are piped to dd, and then written to /dev/hda.

===Copy floppy===
# dd if=/dev/fd0 of=/tmp/floppy.img bs=10240

That will copy the contents of the floppy to a file. Then, to put the image onto a new floppy, swap "if" and "of" params.

# dd if=/tmp/floppy.img of=/dev/fd0 bs=10240

===Backing up your Master Boot Record ([[MBR]]).===
You should do this before you edit your partition table so that you can put it back if you mess things up.

# dd if=/dev/hda of=/root/hda.boot.mbr bs=512 count=1

If things mess up, you can boot with [[Knoppix]], mount the partition containing /root (hda1 in this example) and put back the MBR with the command:

# dd if=/mnt/hda1/root/hda.boot.mbr of=/dev/hda bs=512 count=1

===Getting around file size limitations using split===
When making images, it's quite easy to run up against various file size limitations. One way to work around a given file size limitation is to use the [[split]] command.

# dd if=/dev/hda1 | gzip -c | split -b 2000m - /mnt/hdc1/backup.img.gz.

# This example is using dd to take an image of the first partition on the first harddrive.
# The results are passed through to [[gzip]] for compression
#* The -c option switch is used to output the result to [[stdout]].
# The compressed image is then piped to the [[split]] tool
#* The -b 2000m switch tells split how big to make the individual files. You can use k and m to tell switch kilobytes and megabytes (this option uses bytes by default).
#* The - option tells split to read from [[stdin]]. Otherwise, split would interpret the /mnt/hdc1... as the file to be split.
#* The /mnt/hdc1... is the prefix for the created files. Split will create files named backup.img.gz.aa, backup.img.gz.ab, etc.

To restore the multi-file backup, do the following:

# cat /mnt/hdc1/backup.img.gz.* | gzip -dc | dd of=/dev/hda1

#Cat recombines contents of the compressed and split image files to [[stdout]], in order.
#Results are piped through gzip for decompression.
#And are then written to the first partition of the hard drive with dd.

==Jargon File Entry==
This is what the [[Jargon File]] has to say about dd:

[Unix: from IBM JCL] Equivalent to [[cat]] or BLT. Originally the name of a Unix copy command with special options suitable for [[block device|block-oriented devices]]; it was often used in heavy-handed system maintenance, as in "Let's dd the [[root]] partition onto a tape, then use the boot PROM to load it back on to a new disk". The Unix dd(1)was designed with a weird, distinctly non-Unixy keyword option syntax reminiscent of IBM System/360 JCL (which had an elaborate DD "Dataset Definition" specification for I/O devices); though the command filled a need, the interface design was clearly a prank. The jargon usage is now very rare outside Unix sites and now nearly obsolete even there, as dd(1) has been [[deprecated]] for a long time (though it has no exact replacement). The term has been displaced by BLT or simple English "copy".

''Though how one would deprecate such a useful tool without providing a replacement is beyond me.'' [[User:Crazyeddie|Crazyeddie]] 04:20, Jul 28, 2004 (EDT)

{{Jargon File/Attribution}}

==See also==
* [[image]]
* [[Blanking a hard drive]]
* [[rawrite]]

==External links==
* [http://man.linuxquestions.org/index.php?query=dd&section=0&type=2 dd man page]

Code

2005-01-23T08:11:18Z

Frob23: merged

A synonym for [[source]]. The [[program]] [[text]] that a programmer types into a text [[editor]], which is subsequently either:
* run by an [[interpreter]], or else
* [[compile]]d into either:
** [[bytecode]], then interpreted (possibly by a [[virtual machine]], or
** compiled into a [[machine code]] [[binary]] to be executed directly by the computer.

Code, when used in speech, can be either a verb or a noun.
#n. The stuff that [[software]] writers write, either in source form or after translation by a [[compiler]] or [[assembler]]. Often used in opposition to “data”, which is the stuff that code operates on. Among [[hacker]]s this is a mass noun, as in “How much code does it take to do a bubble sort?”, or “The code is loaded at the high end of [[RAM]].” Among scientific [[programmer]]s it is sometimes a count noun equilvalent to “program”; thus they may speak of “codes” in the plural. Anyone referring to [[software]] as “the software codes” is probably a [[newbie]] or a [[suit]].
#v. To write code. In this sense, always refers to source code rather than compiled. “I coded an [[Emacs]] clone in two hours!” This verb is a bit of a cultural marker associated with the [[Unix]] and [[minicomputer]] traditions (and lately [[Linux]]); people within that culture prefer v. ‘code’ to v. ‘program’ whereas outside it the reverse is normally true.

See also: [[compile]]

{{Jargon File/Attribution}}

User:Frob23

2005-01-23T08:06:05Z

Frob23:

Comment out

2005-01-23T07:55:18Z

Frob23: Change text attribution to template.

To '''comment out''' as piece of code means to surround a section of code with comment delimiters or to prefix every line in the section with a comment marker; this prevents it from being compiled or interpreted. Often done when the code is redundant or obsolete, but is being left in the source to make the intent of the active code clearer; also when the code in that section is broken and you want to bypass it in order to debug some other part of the code. Compare [[condition out]], usually the preferred technique in languages (such as [[C]]) that make it possible.

===Comment Markers in Various Languages===
*Bash
Append <nowiki>#</nowiki> to a line to comment it out.

{{Jargon File/Attribution}}

User talk:Frob23

2005-01-23T07:53:33Z

Frob23:

Code

2005-01-23T07:46:01Z

Frob23: Added Entry from Jargon File.

A synonym for [[source]]. The [[program]] [[text]] that a programmer types into a text [[editor]], which is subsequently either:
* run by an [[interpreter]], or else
* [[compile]]d into either:
** [[bytecode]], then interpreted (possibly by a [[virtual machine]], or
** compiled into a [[machine code]] [[binary]] to be executed directly by the computer.

See also: [[compile]]

----
=Jargon File Definition=
code

#n. The stuff that [[software]] writers write, either in source form or after translation by a [[compiler]] or [[assembler]]. Often used in opposition to “data”, which is the stuff that code operates on. Among [[hacker]]s this is a mass noun, as in “How much code does it take to do a bubble sort?”, or “The code is loaded at the high end of [[RAM]].” Among scientific [[programmer]]s it is sometimes a count noun equilvalent to “program”; thus they may speak of “codes” in the plural. Anyone referring to [[software]] as “the software codes” is probably a [[newbie]] or a [[suit]].
#v. To write code. In this sense, always refers to source code rather than compiled. “I coded an [[Emacs]] clone in two hours!” This verb is a bit of a cultural marker associated with the [[Unix]] and [[minicomputer]] traditions (and lately [[Linux]]); people within that culture prefer v. ‘code’ to v. ‘program’ whereas outside it the reverse is normally true.

{{Jargon File/Attribution}}

C

2005-01-23T07:38:46Z

Frob23: Consistency of placement for attribution.

The '''C''' [[programming language]] is certainly the most influential in the world of [[programming]]. Created at first by [[Brian Kernighan]] and [[Dennis Ritchie]] in 1972, this language is characterized by its closeness to the hardware without being architecture dependent. Not that it is complicated (like [[Assembly]]), but you can move generally as you want in the memory for example, but may crash if you are not permitted to read or write to that memory.

The C language is often associated with [[UNIX]], maybe because it has been developed on and written with it. But it is not linked with any system nor architecture. You can use C in many applications with this language. It, however, has come under criticism for being insecure, when it is not used correctly (for example, bounds overflow checking is not done by default - allowing the chance for buffer overflow attacks in poorly written software). See [[Overrun screw]].

Note that even if it is still the most used, the C language has gradually become an old language. Having been written in 1972 means it was created before many modern studies on programming language theory. These studies provide huge advances in the creation of a language, especially in the precision and speed with which it's [[compile]]d. For example, you don't have a real range of lines and columns when there is an error or a warning in C; recent languages do. However, Kernighan and Ritchie wrote 'The C Programming Language' in 1978, which served as the de facto standard until it was modified as ANSI C in 1988 and formal standards were promulgated in 1990 and 1999 ISO standards. So C has continued to evolve over time.



==Language Features==

===Types===

====Basic Types====
'''char''': character 1 byte -128 to 127 
'''int''': integer 2 byte -32768 to 32767 
'''float''': float 4 byte -3.4E38 to 3.4E38 
'''double''': double float 8 byte -1.8E308 to 1.8E308 
 
'''short''': shorter type 2 byte -32768 to 32767 
'''long''': longer type 4 byte -2147483648 to 2147483647 
 
'''signed''': signed type 
'''unsigned''': unsigned type 
 









===Expressions===
An expression is a series of operators and quantities to be operated on (operands) that returns a result. This result can be used as the operand of a larger expression or assigned into a variable. Expressions are used throughout the language - in <tt>if</tt> statements, loops, function calls - and they can even be statements by themselves.

This last use is interesting. Just <tt>1;</tt> is a valid C statement. Of course, a statement is only interesting if it has side-effects. Saying <tt>a=1;</tt> has the side-effect of assigning the value 1 to the variable <tt>a</tt>. Side-effects are especially important with the logical operations and the tertiary if-then operator.

====Operators====
There are tons of operators in C. Mathematical, bitwise logical, logical, comparison, and a few others. Operators have precedence, meaning that some take effect before others. Parentheses can be used to do things in the order you want.


=====Mathematical=====
The most familiar operators for most people are <tt>+</tt>, <tt>-</tt>, <tt>*</tt> (multiplication) and <tt>÷</tt>. Division uses a slash <tt>/</tt>, and there's also the modulus operator <tt>%</tt> for remainder after integer division. I think of the unary operators <tt>+</tt> and <tt>-</tt> (negative) as mathematical as well.

=====Assignment=====
Assignment operators have the side-effect of setting a variable's value. In addition to the typical <tt>=</tt>, there are several operators like <tt>+=</tt> which means, "Add this to the variable." The assignment operators are <tt>=, +=, -=, *=, /=, %=, &=, ^=, |=, <<=,</tt> and <tt>>>=</tt>.

a += b; // equivalent to a = a + b
a -= b; // equivalent to a = a - b

=====Comparison=====

These operators compare two values, returning 1 for true or 0 for false. The test to see if two values are equal is <tt>(a == b)</tt> with a double equals sign (since a single '=' is used for assignment). The comparison operators are <tt>==, !=</tt> (not equal), <tt><, >, <=,</tt> and <tt>>=</tt>.

A common mistake is the use of something like

if (a = b) { // WRONG!

when it should have been

if (a == b) {

The former will redefine ''a'' equal to ''b'', and use the new value of ''a'' as the condition for the IF statement; so for any non-zero value of ''b'', this will succeed (and mess up ''a'' in the meantime). Watch out for this trap! It's ''one'' = for telling, ''two'' == for asking.

=====Logical=====
Logical operators combine values that are true or false. The key concept is that is not 0 is true, and 0 is false. Each of these operators returns 1 for true.

a && b // test if a AND b are true
a || b // test if a OR b are true
!a // test if the negation of a is true
a ^ b // exclusive-OR; (a || b) && !(a && b)

It is important to realise that '''C''' stops processing an expression as soon as the answer is known for sure -- ''not every sub-expression in a compound expression will necessarily be evaluated''. The expressions a and b can have side-effects like assigning the values of variables. Because of the difficulty in debugging such expressions, the use of function calls and operators with side-effects within logical expressions is discouraged. It is common in [[shell]] scripts to use logical operators as quick-and-dirty if statements.

As an example, if we have an expression such as

if ((a && b) || c) {

if ''a'' is false, ''b'' will not be evaluated (because a && b cannot possibly be true if ''a'' is false). But ''c'' will have to be evaluated, because we do not know the result in advance. If ''a'' is true, ''b'' will be evaluated; and if ''b'' is also true, then ''c'' will ''not'' be evaluated, since we know that the result of the OR operation will be true.

=====Tertiary if-then operator=====
This operator is unique in that it takes three operands. The form is <tt>(a)?(b):(c)</tt>. (Parentheses are recommended because this operator has low precedence.) The operator evaluates <tt>a</tt>, and if it is true, then it returns <tt>b</tt>. Otherwise it returns <tt>c</tt>. If there are side-effects, a regular <tt>if</tt> statement is recommended.

Being an operator, ?: ''does'' return a value. So
d = ((a) ? (b) : (c));
sets ''d'' = ''b'' (and does not evaluate ''c'') if ''a'' is true (i.e. anything but zero), or ''d'' = ''c'' (and does not evaluate ''b'') if ''a'' is false (zero).

=====Bitwise Operators=====
Bitwise operators, as the name suggests, operate on binary numbers on a bit-by-bit basis.

a & b = bitwise AND
a | b = bitwise OR
a ^ c = bitwise XOR (exclusive OR)

Each bit of ''a'' is ANDed, ORed or XORed with the corresponding bit of ''b'' and the answer is inserted in the corresponding bit position in the result. For example, ''(I'm using hexadecimal numbers here to make it a little more obvious -- but this obviously works with any numeric values)''

0xe8 & 0x1f = 0x08
0x51 | 0x60 = 0x71
0xaa ^ 0xff = 0x55

These operators are very useful when storing several boolean values in an integer or char. Also, you can somtimes make use of the fact that -- in ASCII codes -- bit 5 (i.e. the 32's) is ''set'' (1) in the lower case letters, but ''cleared'' (0) in the corresponding capital letter.

=====Bit Shift Operators=====
These operators shift the bits of a binary number to the left or the right. Bits that "fall off the end" are lost for all time, and zeros are shifted into the opposite end.

x = a << b; // bits of a, left hand shifted b times
y = a >> b; // bits of a, right hand shifted b times

These operators are meant to be combined with the bitwise operators above. Suppose we wished to store a day of the week ''day'' (between 0 and 6), a date within the month ''date'' (between 1 and 31), and a month ''month'' (between 1 and 12) in an ''int'' variable ''ddm''. We need 3 bits to store ''day'', 5 bits to store ''date'' and 4 bits to store ''month'', and we could build up an expression like this:

ddm = (day << 9) | (date << 4) | month;

and then the reverse would be

day = ((ddm & 7<<9) >>9);
date = ((ddm & 31<<4) >>4);
month = (ddm & 15);

We use the AND operator to select just the bits we are interested in, the two shift operators to position them where we want, and the OR operator to assemble the groups of bits together.

=====Increment and Decrement=====
The '''++''' and '''--''' operators -- a shorthand notation for adding and subtracting one from a variable -- can each be used in two different ways. If the operator comes ''after'' the variable name, then the variable is incremented or decremented ''after'' its value is read and passed on. If the operator comes ''before'' the variable name, then the variable is modified ''before'' its value is read.

a = b++; // equivalent to a = b; b += 1
a = b--; // equivalent to a = b; b -= 1
a = ++b; // equivalent to b += 1; a = b
a = --b; // equivalent to b -= 1; a = b

=====Other=====
The comma, pointer/structure/array operators, type casts.

===Control structures===

====''if (else)'' instruction====
The general look of a C if-then-else statement is something like 
if(expression){
A
} else {
B
}
If expression is different from 0 then A (whatever that might be) is executed, otherwise, that is expression is 0, B is executed. 
 
The real issue here is of course; what is expression, A and B. expression is from the compilers point of view any value that can be interpreted as a number, that's almost anything in C. For instance the value 2 would be syntactically correct. The key issue is that 2 is different from 0, thus A would be executed. A and B is any piece of code actually, for example <tt>printf("Hello World!");</tt> 
 
Here's an example of an if statement: 

if(customers > 0){
printf("There are people in the shop"); // state the obvious
getHelp(); // call some functions that gets more personnel
} else {
drinkMoreCoffee(); // do what you're trained to do
}

The tertiary operator (above) can be used as a quick form of the if statement.

====''while (do)'' instruction====
The general look of while statement: 

while(expression){
do something
}

expression is the same thing as with if statements, i.e. something that can be evaluated either true (different from zero) or false (that is zero). What's happening here is that we first test if expression is true, if so the body of the while statement is executed as long as expression is true. For example: 

int a = 0;
while(a < 5){
a++;
printf("%d, ", a);
}
printf("\n");

This would produce the output: 

1, 2, 3, 4, 5,

Key note is that whether a is less than 5 or not is just tested in the beginning of the while loop, so it's possible to write the number 5. Then of course the loop is terminated. 
 
The brother while loop is the so called do-while-loop 

do {
do something
} while(expression);

The key note here is that whether expression is true or not is tested at the end of the loop, that means that the body of the loop is executed at least once. 
 
It's of course possible to construct a loop that runs forever (infinite loop). For example: 

int a = 0;
while(a < 3){
printf("I'm a fruitcake\n");
}

====''for'' instruction====
The general look of a for-loop is: 

for(A;B;C){
do something
}

Here A is executed just once when we enter the for-loop, typically to initialize some variables. B is a truth conditional like the ones in the while loop, if B is true then we continue looping. C is executed every time at the end of the loop. For example: 

for(i = 0; i < 5; i++){
printf("%d, ", i);
}
printf("\n");

This would produce the output: 

0, 1, 2, 3, 4,

to guide you through it: First i is set to 0, this happens just once. Then we test if i is less than 5, clearly, it's 0. Now we enter the for-loop and print the value of, i. At the end of the loop i is incremented by 1. Then test again weather i is less than 5, print it's values, and so on. 
 
Please note that A, B and C can all be omitted, This is valid syntax: 

for(;;){
printf("I'm looping forever and I'm happy with it.\n");
}

It's not too common to introduce loops like this, but it works. The idea is that you can do something like:

int i = 0;
for(;i < 10; printf("Hello")){
i++;
}

Also you can do more things in A and C, For example you want to initialize variables i to 0 and j to 5 at the beginning of the loop.

for(i = 1, j = 5; (i*j) > 0; j++, j--){
printf("%d, ", i*j);
}

The , between i = 0 and j = 5 is the separator here. Same style goes at the end where j is incremented and j decremented.

===Functions===
First of all a function can be thought of as a way to store a procedure. This procedure contains some instructions that you want to carry out many times. Also it's a way to structure your program. It can also be regarded as a function in a more mathematical sense. A wide variety of functions are available in the [[standard library]], [[glibc]] (Some of these are actually in the math library, accessed by linking the program with <tt>-lm</tt>).

Here is the general outfit of a C function:

return_type function_name(argument_1, argument_2, ..., argument_n){
function_body
}

A simple example of a function:

int max_i(int a, int b){
if(a > b){
return a;
}
return b;
}

Functions can of course call other functions, for example:

int find_max(int *nums, int len){
int max = 0, i;
for(i = 0; i < len; i++){
max = max_i(nums[i], max);
}
return max;
}

Further functions can call themselves, this example calculates n!.

int fac(int n){
if(n == 1){
return 1;
}
return n*fac(n - 1);
}

Functions can return all basic types such as, int, float, double, char, etc. They can also return pointers to all these. They can return pointers to structs and void. If a function is declared to return void it simply returns nothing. Don't confuse this with functions that returns pointers to void, that is void*. returning void* is simply returning a general pointer to something we don't the type of.

An example of a function that 'returns' void.

void printObvious(){
pritnf("I'm a function that returns nothing.\n");
}

As we can see, we can omit the return statement since this function does not return anything.





==History of C==
C was designed by [[Dennis Ritchie]] during the early 1970s and immediately used to reimplement [[Unix]]. It was called C because many features derived from an earlier [[compiler]] named [[B]] in commemoration of its parent, ]]BCPL\\. (BCPL was in turn descended from an earlier [[Algol]]-derived language, [[CPL]].) Before Bjarne Stroustrup settled the question by designing [[C plus plus|C++]], there was a humorous debate over whether C's successor should be named ‘D’ or ‘P’. C became immensely popular outside Bell Labs after about 1980 and is now the dominant language in systems and microcomputer applications programming. C is often described, with a mixture of fondness and disdain varying according to the speaker, as “a language that combines all the elegance and power of [[assembly language]] with all the readability and maintainability of assembly language”. C has for a long time been one of the [[languages of choice]]. See also [[History of Unix]], [[ident style]].

==Books==
*''C Programming Language'', Brian W. Kernighan, [[Dennis Ritchie]]
*''C: A Reference Manual'', Samuel P. Harbison, Guy L. Steele
*''The C Puzzle Book'', Alan R. Feuer

For beginning users:
*''C How to Program'', by Dietel et al. (Only the first two versions are recommended by [[User:Crazyeddie|my]] source.)
*''Practical C Programming'', by Steve Oualline

==Tutorial Material==
Since this page serves as something of language overview, more lengthy examples would fit better on their own page. Check out [[CProgrammingExamples]] for some examples, that might help you getting started with C programming.

==See also==
*[[Programming#Compiled languages|Compiled languages section]]

==External links==

{{Jargon File/Attribution}}

C plus plus

2005-01-23T07:37:58Z

Frob23: Change text attribution to template.

'''C++''' is a very popular [[programming language]] (an extension of the original [[C]]) that is commonly used to program many of [[GNU/Linux]]'s core programs. It's often used to write [[object-oriented]] software.

==History==
It was designed by Bjarne Stroustrup of AT&T Bell Labs as a successor to [[C]]. Now one of the [[languages of choice]], although many [[hacker]]s still grumble that it is the successor to either [[Algol]] 68 or [[Ada]] (depending on generation), and a prime example of [[second-system effect]]. Almost anything that can be done in any language can be done in C++, but it requires a [[language lawyer]] to know what is and what is not legal — the design is almost too large to hold in even hackers' heads. Much of the [[cruft]] results from C++'s attempt to be [[backward compatible]] with C. Stroustrup himself has said in his retrospective book The Design and Evolution of C++ (p. 207), “Within C++, there is a much smaller and cleaner language struggling to get out.” [Many hackers would now add “Yes, and it's called [[Java]]” —[[ESR]]]

==Language features==

* strong type checking
* namespaces
* templates
* operator overloading
* exception handling
* The standard library
** STL
*** containers
*** generic algorithms
*** iterators
** strings
** streams
** numerics
** The entire C standard library

==Examples==
<tt><pre>
// A very small C++ program.
#include <iostream>
int main()
{
std::cout << "Hello, world!" << std::endl;
return 0;
}
</pre></tt>

This displays the phrase "Hello, world!" on the screen, similar to the simpler shell command "echo Hello, world!" used in the Linux console.

==Further reading==

==Books==
*''The C++ Programming Language'', Bjarne Stroustrup
*''Effective C++: 50 Specific Ways to Improve Your Programs and Design'', [http://www.aristeia.com/ Scott Meyers]
*''Code Complete'', Steve McConnell
*''Accelerated C++'', Andrew Koenig & Barbara E. Moo

==See also==
*[[Programming#Compiled languages|Compiled languages section]]
*[[C]]
*[[C/C_plus_plus tips|C and C++ tips]]
*[[C plus plus tutorial|C++ tutorial]]
*[[C plus plus practices|Good Programming Practices]]
*[[Programming-related_Commands]]
*[[C plus plus tools|Linux C++ tools]]

==External links==
*[http://www.cplusplus.com/doc/tutorial/ A complete C++ language tutorial]

{{stub}}

{{Jargon File/Attribution}}

C

2005-01-23T07:37:11Z

Frob23: /* History of C */ Added template in place of text attribution

The '''C''' [[programming language]] is certainly the most influential in the world of [[programming]]. Created at first by [[Brian Kernighan]] and [[Dennis Ritchie]] in 1972, this language is characterized by its closeness to the hardware without being architecture dependent. Not that it is complicated (like [[Assembly]]), but you can move generally as you want in the memory for example, but may crash if you are not permitted to read or write to that memory.

The C language is often associated with [[UNIX]], maybe because it has been developed on and written with it. But it is not linked with any system nor architecture. You can use C in many applications with this language. It, however, has come under criticism for being insecure, when it is not used correctly (for example, bounds overflow checking is not done by default - allowing the chance for buffer overflow attacks in poorly written software). See [[Overrun screw]].

Note that even if it is still the most used, the C language has gradually become an old language. Having been written in 1972 means it was created before many modern studies on programming language theory. These studies provide huge advances in the creation of a language, especially in the precision and speed with which it's [[compile]]d. For example, you don't have a real range of lines and columns when there is an error or a warning in C; recent languages do. However, Kernighan and Ritchie wrote 'The C Programming Language' in 1978, which served as the de facto standard until it was modified as ANSI C in 1988 and formal standards were promulgated in 1990 and 1999 ISO standards. So C has continued to evolve over time.



==Language Features==

===Types===

====Basic Types====
'''char''': character 1 byte -128 to 127 
'''int''': integer 2 byte -32768 to 32767 
'''float''': float 4 byte -3.4E38 to 3.4E38 
'''double''': double float 8 byte -1.8E308 to 1.8E308 
 
'''short''': shorter type 2 byte -32768 to 32767 
'''long''': longer type 4 byte -2147483648 to 2147483647 
 
'''signed''': signed type 
'''unsigned''': unsigned type 
 









===Expressions===
An expression is a series of operators and quantities to be operated on (operands) that returns a result. This result can be used as the operand of a larger expression or assigned into a variable. Expressions are used throughout the language - in <tt>if</tt> statements, loops, function calls - and they can even be statements by themselves.

This last use is interesting. Just <tt>1;</tt> is a valid C statement. Of course, a statement is only interesting if it has side-effects. Saying <tt>a=1;</tt> has the side-effect of assigning the value 1 to the variable <tt>a</tt>. Side-effects are especially important with the logical operations and the tertiary if-then operator.

====Operators====
There are tons of operators in C. Mathematical, bitwise logical, logical, comparison, and a few others. Operators have precedence, meaning that some take effect before others. Parentheses can be used to do things in the order you want.


=====Mathematical=====
The most familiar operators for most people are <tt>+</tt>, <tt>-</tt>, <tt>*</tt> (multiplication) and <tt>÷</tt>. Division uses a slash <tt>/</tt>, and there's also the modulus operator <tt>%</tt> for remainder after integer division. I think of the unary operators <tt>+</tt> and <tt>-</tt> (negative) as mathematical as well.

=====Assignment=====
Assignment operators have the side-effect of setting a variable's value. In addition to the typical <tt>=</tt>, there are several operators like <tt>+=</tt> which means, "Add this to the variable." The assignment operators are <tt>=, +=, -=, *=, /=, %=, &=, ^=, |=, <<=,</tt> and <tt>>>=</tt>.

a += b; // equivalent to a = a + b
a -= b; // equivalent to a = a - b

=====Comparison=====

These operators compare two values, returning 1 for true or 0 for false. The test to see if two values are equal is <tt>(a == b)</tt> with a double equals sign (since a single '=' is used for assignment). The comparison operators are <tt>==, !=</tt> (not equal), <tt><, >, <=,</tt> and <tt>>=</tt>.

A common mistake is the use of something like

if (a = b) { // WRONG!

when it should have been

if (a == b) {

The former will redefine ''a'' equal to ''b'', and use the new value of ''a'' as the condition for the IF statement; so for any non-zero value of ''b'', this will succeed (and mess up ''a'' in the meantime). Watch out for this trap! It's ''one'' = for telling, ''two'' == for asking.

=====Logical=====
Logical operators combine values that are true or false. The key concept is that is not 0 is true, and 0 is false. Each of these operators returns 1 for true.

a && b // test if a AND b are true
a || b // test if a OR b are true
!a // test if the negation of a is true
a ^ b // exclusive-OR; (a || b) && !(a && b)

It is important to realise that '''C''' stops processing an expression as soon as the answer is known for sure -- ''not every sub-expression in a compound expression will necessarily be evaluated''. The expressions a and b can have side-effects like assigning the values of variables. Because of the difficulty in debugging such expressions, the use of function calls and operators with side-effects within logical expressions is discouraged. It is common in [[shell]] scripts to use logical operators as quick-and-dirty if statements.

As an example, if we have an expression such as

if ((a && b) || c) {

if ''a'' is false, ''b'' will not be evaluated (because a && b cannot possibly be true if ''a'' is false). But ''c'' will have to be evaluated, because we do not know the result in advance. If ''a'' is true, ''b'' will be evaluated; and if ''b'' is also true, then ''c'' will ''not'' be evaluated, since we know that the result of the OR operation will be true.

=====Tertiary if-then operator=====
This operator is unique in that it takes three operands. The form is <tt>(a)?(b):(c)</tt>. (Parentheses are recommended because this operator has low precedence.) The operator evaluates <tt>a</tt>, and if it is true, then it returns <tt>b</tt>. Otherwise it returns <tt>c</tt>. If there are side-effects, a regular <tt>if</tt> statement is recommended.

Being an operator, ?: ''does'' return a value. So
d = ((a) ? (b) : (c));
sets ''d'' = ''b'' (and does not evaluate ''c'') if ''a'' is true (i.e. anything but zero), or ''d'' = ''c'' (and does not evaluate ''b'') if ''a'' is false (zero).

=====Bitwise Operators=====
Bitwise operators, as the name suggests, operate on binary numbers on a bit-by-bit basis.

a & b = bitwise AND
a | b = bitwise OR
a ^ c = bitwise XOR (exclusive OR)

Each bit of ''a'' is ANDed, ORed or XORed with the corresponding bit of ''b'' and the answer is inserted in the corresponding bit position in the result. For example, ''(I'm using hexadecimal numbers here to make it a little more obvious -- but this obviously works with any numeric values)''

0xe8 & 0x1f = 0x08
0x51 | 0x60 = 0x71
0xaa ^ 0xff = 0x55

These operators are very useful when storing several boolean values in an integer or char. Also, you can somtimes make use of the fact that -- in ASCII codes -- bit 5 (i.e. the 32's) is ''set'' (1) in the lower case letters, but ''cleared'' (0) in the corresponding capital letter.

=====Bit Shift Operators=====
These operators shift the bits of a binary number to the left or the right. Bits that "fall off the end" are lost for all time, and zeros are shifted into the opposite end.

x = a << b; // bits of a, left hand shifted b times
y = a >> b; // bits of a, right hand shifted b times

These operators are meant to be combined with the bitwise operators above. Suppose we wished to store a day of the week ''day'' (between 0 and 6), a date within the month ''date'' (between 1 and 31), and a month ''month'' (between 1 and 12) in an ''int'' variable ''ddm''. We need 3 bits to store ''day'', 5 bits to store ''date'' and 4 bits to store ''month'', and we could build up an expression like this:

ddm = (day << 9) | (date << 4) | month;

and then the reverse would be

day = ((ddm & 7<<9) >>9);
date = ((ddm & 31<<4) >>4);
month = (ddm & 15);

We use the AND operator to select just the bits we are interested in, the two shift operators to position them where we want, and the OR operator to assemble the groups of bits together.

=====Increment and Decrement=====
The '''++''' and '''--''' operators -- a shorthand notation for adding and subtracting one from a variable -- can each be used in two different ways. If the operator comes ''after'' the variable name, then the variable is incremented or decremented ''after'' its value is read and passed on. If the operator comes ''before'' the variable name, then the variable is modified ''before'' its value is read.

a = b++; // equivalent to a = b; b += 1
a = b--; // equivalent to a = b; b -= 1
a = ++b; // equivalent to b += 1; a = b
a = --b; // equivalent to b -= 1; a = b

=====Other=====
The comma, pointer/structure/array operators, type casts.

===Control structures===

====''if (else)'' instruction====
The general look of a C if-then-else statement is something like 
if(expression){
A
} else {
B
}
If expression is different from 0 then A (whatever that might be) is executed, otherwise, that is expression is 0, B is executed. 
 
The real issue here is of course; what is expression, A and B. expression is from the compilers point of view any value that can be interpreted as a number, that's almost anything in C. For instance the value 2 would be syntactically correct. The key issue is that 2 is different from 0, thus A would be executed. A and B is any piece of code actually, for example <tt>printf("Hello World!");</tt> 
 
Here's an example of an if statement: 

if(customers > 0){
printf("There are people in the shop"); // state the obvious
getHelp(); // call some functions that gets more personnel
} else {
drinkMoreCoffee(); // do what you're trained to do
}

The tertiary operator (above) can be used as a quick form of the if statement.

====''while (do)'' instruction====
The general look of while statement: 

while(expression){
do something
}

expression is the same thing as with if statements, i.e. something that can be evaluated either true (different from zero) or false (that is zero). What's happening here is that we first test if expression is true, if so the body of the while statement is executed as long as expression is true. For example: 

int a = 0;
while(a < 5){
a++;
printf("%d, ", a);
}
printf("\n");

This would produce the output: 

1, 2, 3, 4, 5,

Key note is that whether a is less than 5 or not is just tested in the beginning of the while loop, so it's possible to write the number 5. Then of course the loop is terminated. 
 
The brother while loop is the so called do-while-loop 

do {
do something
} while(expression);

The key note here is that whether expression is true or not is tested at the end of the loop, that means that the body of the loop is executed at least once. 
 
It's of course possible to construct a loop that runs forever (infinite loop). For example: 

int a = 0;
while(a < 3){
printf("I'm a fruitcake\n");
}

====''for'' instruction====
The general look of a for-loop is: 

for(A;B;C){
do something
}

Here A is executed just once when we enter the for-loop, typically to initialize some variables. B is a truth conditional like the ones in the while loop, if B is true then we continue looping. C is executed every time at the end of the loop. For example: 

for(i = 0; i < 5; i++){
printf("%d, ", i);
}
printf("\n");

This would produce the output: 

0, 1, 2, 3, 4,

to guide you through it: First i is set to 0, this happens just once. Then we test if i is less than 5, clearly, it's 0. Now we enter the for-loop and print the value of, i. At the end of the loop i is incremented by 1. Then test again weather i is less than 5, print it's values, and so on. 
 
Please note that A, B and C can all be omitted, This is valid syntax: 

for(;;){
printf("I'm looping forever and I'm happy with it.\n");
}

It's not too common to introduce loops like this, but it works. The idea is that you can do something like:

int i = 0;
for(;i < 10; printf("Hello")){
i++;
}

Also you can do more things in A and C, For example you want to initialize variables i to 0 and j to 5 at the beginning of the loop.

for(i = 1, j = 5; (i*j) > 0; j++, j--){
printf("%d, ", i*j);
}

The , between i = 0 and j = 5 is the separator here. Same style goes at the end where j is incremented and j decremented.

===Functions===
First of all a function can be thought of as a way to store a procedure. This procedure contains some instructions that you want to carry out many times. Also it's a way to structure your program. It can also be regarded as a function in a more mathematical sense. A wide variety of functions are available in the [[standard library]], [[glibc]] (Some of these are actually in the math library, accessed by linking the program with <tt>-lm</tt>).

Here is the general outfit of a C function:

return_type function_name(argument_1, argument_2, ..., argument_n){
function_body
}

A simple example of a function:

int max_i(int a, int b){
if(a > b){
return a;
}
return b;
}

Functions can of course call other functions, for example:

int find_max(int *nums, int len){
int max = 0, i;
for(i = 0; i < len; i++){
max = max_i(nums[i], max);
}
return max;
}

Further functions can call themselves, this example calculates n!.

int fac(int n){
if(n == 1){
return 1;
}
return n*fac(n - 1);
}

Functions can return all basic types such as, int, float, double, char, etc. They can also return pointers to all these. They can return pointers to structs and void. If a function is declared to return void it simply returns nothing. Don't confuse this with functions that returns pointers to void, that is void*. returning void* is simply returning a general pointer to something we don't the type of.

An example of a function that 'returns' void.

void printObvious(){
pritnf("I'm a function that returns nothing.\n");
}

As we can see, we can omit the return statement since this function does not return anything.





==History of C==
C was designed by [[Dennis Ritchie]] during the early 1970s and immediately used to reimplement [[Unix]]. It was called C because many features derived from an earlier [[compiler]] named [[B]] in commemoration of its parent, ]]BCPL\\. (BCPL was in turn descended from an earlier [[Algol]]-derived language, [[CPL]].) Before Bjarne Stroustrup settled the question by designing [[C plus plus|C++]], there was a humorous debate over whether C's successor should be named ‘D’ or ‘P’. C became immensely popular outside Bell Labs after about 1980 and is now the dominant language in systems and microcomputer applications programming. C is often described, with a mixture of fondness and disdain varying according to the speaker, as “a language that combines all the elegance and power of [[assembly language]] with all the readability and maintainability of assembly language”. C has for a long time been one of the [[languages of choice]]. See also [[History of Unix]], [[ident style]].

{{Jargon File/Attribution}}

==Books==
*''C Programming Language'', Brian W. Kernighan, [[Dennis Ritchie]]
*''C: A Reference Manual'', Samuel P. Harbison, Guy L. Steele
*''The C Puzzle Book'', Alan R. Feuer

For beginning users:
*''C How to Program'', by Dietel et al. (Only the first two versions are recommended by [[User:Crazyeddie|my]] source.)
*''Practical C Programming'', by Steve Oualline

==Tutorial Material==
Since this page serves as something of language overview, more lengthy examples would fit better on their own page. Check out [[CProgrammingExamples]] for some examples, that might help you getting started with C programming.

==See also==
*[[Programming#Compiled languages|Compiled languages section]]

==External links==

Burn

2005-01-23T06:11:15Z

Frob23: Change text attribution to template.

To '''Burn''' something in [[computer]] terms, usually refers to copying a [[file]] on a computer, to a [[disk]] [[media]], where in order to get the file on the disk, a [[laser]] is used to "burn" it on the disk.

For example, '''to burn a cd''' means to write a software or document distribution on a [[CDR]]. Coined from the fact that a laser is used to inscribe the information by burning small pits in the medium, and from the fact that disk comes out of the drive warm to the touch. Writable CDs can be done on a normal desk-top machine with a suitable drive (so there is no protracted release cycle associated with making them) but each one takes a long time to make, so they are not appropriate for volume production. Writable CDs are suitable for software backups and for short-turnaround-time low-volume software distribution, such as sending a beta release version to a few selected field test sites. Compare [[cut a tape]].

==Also See==
*[[Burning a CD]] - list of commands to burn [[CD]]'s

{{Jargon File/Attribution}}

Boot

2005-01-23T06:07:59Z

Frob23: Added jargon file template.

'''Boot''', short for '''bootstrapping''', describes the initial phase of starting a computer from power-off, or the process of starting an [[operating system]].

The term comes from the phrase "by one's bootstraps".

The derivative [[reboot]] implies that the machine hasn't been down for long, or that the boot is a [[bounce]] (sense 4) intended to clear some state of [[wedgitude]]. This is sometimes used of human thought processes, as in the following exchange: “You've lost me.” “OK, reboot. Here's the theory....”

This term is also found in the variants [[cold boot]] (from power-off condition) and [[warm boot]] (with the CPU and all devices already powered up, as after a hardware reset or software [[crash]]).

Another variant: [[soft boot]], reinitialization of only part of a system, under control of other software still running: “If you're running the [[mess-dos]] [[emulator]], control-alt-insert will cause a soft-boot of the emulator, while leaving the rest of the system running.”

Opposed to this there is hard boot, which connotes hostility towards or frustration with the machine being booted: “I'll have to hard-boot this losing Sun.” “I recommend booting it hard.” One often hard-boots by performing a [[power cycle]].

===Historical note===
This term derives from "bootstrap loader", a short program that was read in from [[punch card]]s or [[paper tape]], or toggled in from the front panel switches. This program was always very short (great efforts were expended on making it short in order to minimize the labor and chance of error involved in toggling it in), but was just smart enough to read in a slightly more complex program (usually from a card or paper tape reader), to which it handed control; this program in turn was smart enough to read the application or operating system from a magnetic tape drive or disk drive. Thus, in successive steps, the computer ‘pulled itself up by its bootstraps’ to a useful operating state. Nowadays the bootstrap is usually found in [[ROM]] or [[EPROM]], and reads the first stage in from a fixed location on the disk, called the [[MBR]] (Master Boot Record). When this program gains control, it is powerful enough to load the actual OS and hand control over to it.

==Boot Loaders==
* [[GRUB]]
* [[LILO]]

==Other meanings==
/[[boot (directory)|boot]] is a standard high level directory.

==External links==
*[http://www.linux.com/article.pl?sid=04/06/23/1734235 How Linux Boots]

{{stub}}

{{Jargon File/Attribution}}

Bare metal

2005-01-23T05:37:32Z

Frob23: Change text attribution to template.

'''Bare metal''' is new computer hardware, unadorned with such snares and delusions as an [[operating system]], an [[HLL]], or even [[assembler]]. Commonly used in the phrase programming on the bare metal, which refers to the arduous work of [[bit bashing]] needed to create these basic tools for a new machine. Real bare-metal programming involves things like building boot [[prom]]s and [[BIOS]] chips, implementing basic monitors used to test device [[driver]]s, and writing the assemblers that will be used to write the [[compiler]] back ends that will give the new machine a real [[development environment]].

“Programming on the bare metal” is also used to describe a style of [[hand-hacking]] that relies on bit-level peculiarities of a particular hardware design, esp. tricks for speed and space optimization that rely on crocks such as overlapping instructions (or, as in the famous case described in The [[Story of Mel]], interleaving of opcodes on a magnetic [[drum memory|drum]] to minimize fetch delays due to the device's rotational latency). This sort of thing has become rare as the relative costs of programming time and machine resources have changed, but is still found in heavily constrained environments such as industrial [[embedded system]]s.

==See also==
*[[Real Programmer]]

{{Jargon File/Attribution}}

Background

2005-01-23T05:27:36Z

Frob23: Change text attribution to template.

To do a task in '''background''' is to do it whenever [[foreground]] matters are not claiming your undivided attention, and to background something means to relegate it to a lower [[priority]]. “For now, we'll just print a list of nodes and links; I'm working on the graph-printing problem in background.” Note that this implies ongoing activity but at a reduced level or in spare time, in contrast to mainstream ‘back burner’ (which connotes benign neglect until some future resumption of activity). Some people prefer to use the term for processing that they have queued up for their unconscious minds (a tack that one can often fruitfully take upon encountering an obstacle in creative work). Compare [[amp off]], [[slopsucker]].

Technically, a task running in background is detached from the terminal where it was started (and often running at a lower priority); oppose [[foreground]]. Nowadays this term is primarily associated with [[Unix]], but it appears to have been first used in this sense on OS/360.

{{stub}}

{{Jargon File/Attribution}}

Awk

2005-01-22T06:05:46Z

Frob23: First line is from Jargon File concerning the authors.

'''awk''' is a [[C]]-like text processing scripting language originally created in 1977 at AT&T Bell Laboratories by Alfred V. Aho, Peter J. Weinberger, and Brian W. Kernighan. In its modern [[GNU]] incarnation, it implements regular expressions, redirection (including bidirectional communication with coprocesses), user-defined functions, arrays, TCP/IP networking, and floating point math, among other things. [[Awk tips]] provides some quick-and-dirty awk scripts.

==Usage==

When <tt>awk</tt> is run, it is given two forms of input, the ''program'' and the ''data''. The program can be typed directly on the [[command line]] or stored in a file and accessed with the <tt>-f</tt> option. The data comes from [[file]]s listed on the command line or from [[stdin]] if none are listed. The first example has the script on the command line with input from a file, while the second example uses an external program to create the input data and pipes into <tt>awk</tt>, which uses an external script as the program.

$ awk '{ print $1; }' ''datafile''

$ ''makedata'' | awk -f ''myscript.awk''

<tt>awk</tt> scripts that are saved in files can be executed directly by placing the proper [[shebang]] line at the beginning:
#!/bin/awk -f
'''Important note:''' use the exact path of your awk (available from typing "<tt>[[which]] awk</tt>") if it is not named <tt>/bin/awk</tt>.

==Language structure==

An awk program consists of a series of statements each consisting of a ''pattern'' and an ''action''. Awk reads the input (whether [[file]]s or data [[pipe]]d from [[stdin]]) line-by-line automatically. For each line of data, if the ''pattern'' is true, the ''action'' is executed. There are a few special patterns. The <tt>BEGIN</tt> rule is executed first, before any input is read, and the <tt>END</tt> rule is executed last, after the end of all input. Some complicated awk scripts consist of only a <tt>BEGIN</tt> rule and use <tt>getline</tt> to read the input data. If ''pattern'' is empty, the ''action'' is always executed. If ''action'' is empty, awk echos the line.

The pattern can be a [[regular expression]] enclosed in slashes ('/'), in which case it is considered true if the input line matches (i.e. contains matching text) the pattern. The expression <tt>/^[^#]/</tt> would select all lines not beginning with a pound sign. The pattern could also be an awk expression, e.g. <tt>(NF>5)</tt> to select all lines with more than 5 words.

Whenever a line of input is read (whether automatically or with <tt>getline</tt> [http://www.gnu.org/software/gawk/manual/html_node/Getline.html]), the line is split into words. The first word is assigned to <tt>$1</tt>, the second <tt>$2</tt>, etc. This makes it easy for awk to deal with columns of data. The variable <tt>NF</tt> is set to the number of words. <tt>$</tt> is an awk operator, so the "number" can be the result of any expression. <tt>$NF</tt> is the last word on the line.

For a complete description of the language, see the GNU awk manual [http://www.gnu.org/software/gawk/manual/html_node/index.html].

==GNU Awk extensions==

Things to be careful about when using a <tt>gawk</tt> script in a non-GNU awk include:
* Special files like <tt>/dev/stderr</tt>, useful for printing error messages.
* The <tt>systime()</tt> and <tt>strftime()</tt> functions.
* The <tt>nextfile</tt> statement.
* <tt>delete ARRA</tt> to delete an entire array.
* The <tt>gensub()</tt> function.
* Bidirectional pipes to coprocesses.
This list is not comprehensive; the gawk manual (below) has more info.

==See also==
*[[Programming#Scripting languages|Scripting languages section]]

{{Jargon File/Attribution}}

==External links==

*[http://www.gnu.org/software/gawk/manual/html_node/index.html gawk manual] - Excellent reference, especially the sections on Reading Files, Expressions, and Functions.
*[http://man.linuxquestions.org/index.php?query=gawk&section=0&type=2 gawk man page]
*[http://www.tek-tips.com/threadminder.cfm?pid=271 awk forum] - when you have questions
*[http://sparky.rice.edu/~hartigan/awk.html How to Use AWK] - quick intro
*[http://www.cs.uu.nl/docs/vakken/st/nawk/nawk_toc.html awk manual] - shorter than the gawk manual above

ASCII art

2005-01-22T05:58:36Z

Frob23: Changed text attribution to template.

'''ASCII art''' is the fine art of drawing diagrams using the [[ASCII]] character set (mainly |, -, /, \, and +). Also known as character graphics or ASCII graphics; see also [[boxology]].

===Power supply===

o----)||(--+--|<----+ +---------o + D O
L )||( | | | C U
A I )||( +-->|-+ | +-\/\/-+--o - T
C N )||( | | | | P
E )||( +-->|-+--)---+--|(--+-o U
)||( | | | GND T
o----)||(--+--|<----+----------+

A power supply consisting of a full wave rectifier circuit feeding a capacitor input filter circuit.

===Silly Examples===

|\/\/\/| ____/| ___ |\_/| ___
| | \ o.O| ACK! / \_ |` '| _/ \
| | =(_)= THPHTH! / \/ \/ \
| (o)(o) U / \
C _) (__) \/\/\/\ _____ /\/\/\/
| ,___| (oo) \/ \/
| / \/-------\ U (__)
/____\ || | \ /---V `v'- oo )
/ \ ||---W|| * * |--| || |`. |_/\

//-o-\\
____---=======---____
====___\ /.. ..\ /___==== Klingons rule OK!
// ---\__O__/--- \\
\_\ /_/

===Rebuses===
There is an important subgenre of ASCII art that puns on the standard character names in the fashion of a rebus. ''Need to fix formatting...''

+--------------------------------------------------------+
| ^^^^^^^^^^^^ |
| ^^^^^^^^^^^ ^^^^^^^^^ |
| ^^^^^^^^^^^^^ ^^^^^^^^^^^^^ |
| ^^^^^^^ B ^^^^^^^^^ |
| ^^^^^^^^^ ^^^ ^^^^^^^^^^^^^^ |
+--------------------------------------------------------+
" A Bee in the Carrot Patch "

===Silly Cows===
Within humorous ASCII art, there is for some reason an entire flourishing subgenre of pictures of silly cows. Four of these are reproduced in the examples above, here are three more:

(__) (__) (__)
(\/) ($$) (**)
/-------\/ /-------\/ /-------\/
/ | 666 || / |=====|| / | ||
* ||----|| * ||----|| * ||----||
~~ ~~ ~~ ~~ ~~ ~~
Satanic cow This cow is a Yuppie Cow in love

===Train Station===
Finally, here's a magnificent example of ASCII art depicting an Edwardian train station in Dunedin, New Zealand: ''Also need to fix formatting''

.-.
/___\
|___|
|]_[|
/ I \
JL/ | \JL
.-. i () | () i .-.
|_| .^. /_\ LJ=======LJ /_\ .^. |_|
._/___\._./___\_._._._._.L_J_/.-. .-.\_L_J._._._._._/___\._./___\._._._
., |-,-| ., L_J |_| [I] |_| L_J ., |-,-| ., .,
JL |-O-| JL L_J%%%%%%%%%%%%%%%L_J JL |-O-| JL JL
IIIIII_HH_'-'-'_HH_IIIIII|_|=======H=======|_|IIIIII_HH_'-'-'_HH_IIIIII_HH_
-------[]-------[]-------[_]----\.=I=./----[_]-------[]-------[]--------[]-
_/\_ ||\\_I_//|| _/\_ [_] []_/_L_J_\_[] [_] _/\_ ||\\_I_//|| _/\_ ||\
|__| ||=/_|_\=|| |__|_|_| _L_L_J_J_ |_|_|__| ||=/_|_\=|| |__| ||-
|__| |||__|__||| |__[___]__--__===__--__[___]__| |||__|__||| |__| |||
IIIIIII[_]IIIII[_]IIIIIL___J__II__|_|__II__L___JIIIII[_]IIIII[_]IIIIIIII[_]
\_I_/ [_]\_I_/[_] \_I_[_]\II/[]\_\I/_/[]\II/[_]\_I_/ [_]\_I_/[_] \_I_/ [_]
./ \.L_J/ \L_J./ L_JI I[]/ \[]I IL_J \.L_J/ \L_J./ \.L_J
| |L_J| |L_J| L_J| |[]| |[]| |L_J |L_J| |L_J| |L_J
|_____JL_JL___JL_JL____|-|| |[]| |[]| ||-|_____JL_JL___JL_JL_____JL_J

The next step beyond static tableaux in ASCII art is ASCII animation. There are not many large examples of this; perhaps the best known is the ASCII animation of the original Star Wars movie at http://www.asciimation.co.nz/.

There is a [[newsgroup]], alt.ascii-art, devoted to this genre; however, see also [[warlording]].

{{Jargon File/Attribution}}

App

2005-01-22T05:50:33Z

Frob23: Changed text attribution to template.

'''App''' is short for ‘[[application]] program’, as opposed to a systems program. Apps are what systems vendors are forever chasing [[developer]]s to create for their environments so they can sell more [[box]]es. [[Hacker]]s tend not to think of the things they themselves run as apps; thus, in hacker parlance the term excludes [[compiler]]s, program [[editor]]s, [[game]]s, and [[instant messaging|messaging system]]s, though a [[user]] would consider all those to be apps. (Broadly, an app is often a self-contained environment for performing some well-defined task such as ‘[[word processor|word processing]]’; hackers tend to prefer more general-purpose [[tool]]s.)

==See Also==
*[[killer app]]
*[[operating system]]

{{Jargon File/Attribution}}

Adventure

2005-01-22T05:31:17Z

Frob23: Changed text attribution to template.

'''Adventure''' is a common "interactive fiction" text-based [[game]] which leads you through an imaginary world collecting treasures.

Adventure is an incarnation of ADVENT, the prototypical computer adventure game, first designed by Will Crowther on the [[PDP-10]] in the mid-1970s as an attempt at computer-refereed fantasy gaming, and expanded into a puzzle-oriented game by Don Woods at Stanford in 1976. (Woods had been one of the authors of [[INTERCAL]].) Now better known as Adventure or Colossal Cave Adventure, but the [[TOPS-10]] operating system permitted only six-letter filenames in uppercase. See also [[vadding]], [[Zork]], and [[Infocom]].

Other games influnced by ADVENT/Adventure are [[nethack]], [[rouge]], and [[moria]].

=== Sample transcript===
<tt>
You are standing at the end of a road before a small brick building.
Around you is a forest. A small stream flows out of the building and
down a gully. 
go inside

You are inside a building, a well house for a large spring.

There are some keys on the ground here.

There is a shiny brass lamp nearby.

There is food here.

There is a bottle of water here.
</tt>

...

===More Background===
This game defined the terse, dryly humorous style since expected in text adventure games, and popularized several tag lines that have become fixtures of [[hacker]]-speak: “A huge green fierce snake bars the way!” “I see no X here” (for some noun X). “You are in a maze of twisty little passages, all alike.” “You are in a little maze of twisty passages, all different.” The ‘magic words’ [[xyzzy]] and [[plugh]] also derive from this game.

Crowther, by the way, participated in the exploration of the Mammoth & Flint Ridge cave system; it actually has a Colossal Cave and a Bedquilt as in the game, and the Y2 that also turns up is cavers' jargon for a map reference to a secondary entrance.

ADVENT sources are available for FTP at ftp://ftp.wustl.edu/doc/misc/if-archive/games/source/advent.tar.Z . You can also play it as a Java applet. There is a good page of resources at the [http://www.rickadams.org/adventure/ Colossal Cave Adventure Page].

{{Jargon File/Attribution}}

User:Frob23

2005-01-21T23:36:35Z

Frob23:

=frob23=

Often known in real life and in virtual life as Eric Fenderson, although neither of those are included in his actual given name. Eric Fenderson is obsessed with Unix in all its forms. He swears each night before falling off to sleep that he will, one day, port V7 to modern hardware.

[[Frob]] is an action of mindless fiddling with something (usually physical). This is the root word from which I take my user-name. I've used it for a long, long time mainly because a lot of my computer activities were mindless fiddling. Stuff like adding a password to command.com or changing the commands DOS used. Mindless stuff which I continued to do when I moved on to real operating systems. The wonderful thing about frobbing is that often you learn a lot by playing around without intending to learn anything from it.

I spent three years working towards a computer engineering major before I realized that it was not for me. Surprisingly (to myself at the time) my experience with Linux benefited me in that major because all of the work was done on *nix machines. I found [[FreeBSD]] during that time and have been using it steadily ever since but I still have an affection for Linux... she was my first.

I like the wiki and would add more but most of the areas where I could add information would be in the Jargon definitions. And, as it has been pointed out, it is important to not allow them to overwhelm the real information this wiki contains. There are good online sources for the Jargon file.

I have been obsessed with [[Hacker]] [[jargon]] and information ever since I found a hard copy of The New Hacker's Dictionary (version 1) at a local library. This was many years ago but I remember it gave me a vision of something deeper in the mindless tooling around with computers I was doing. I have since obtained hard copies of it and the two subsequent versions for myself. And, when the library moved across town, I was even able to purchase the worn original for $4.00 from the library because they were going to throw it out.

Almost accidentally, I have found myself fitting the description of a Hacker from the appendix. Right down to being a Theater Technician -- which at the time was something I decided to do to avoid the stereotype I saw myself fitting.

So, anyway, clearly I would love to share the source with those who are coming behind and don't know the joy. When I first heard the -[[P convention]] in real life it brought a smile to my face. It made me realize that I am part of a tradition that came before me and will go on beyond me. I want to share that with others.

Well, that's a rambling user page.

--[[User:Frob23|Frob23]] 22:26, Jan 20, 2005 (EST)

Note to self: check admin at work and start below that.

Talk:List of Jargon File Entries

2005-01-21T23:28:27Z

Frob23:

Please put deleted entries here, so if anybody disagrees, they can put them back in. [[User:Crazyeddie|Crazyeddie]] 18:12, Jul 14, 2004 (EDT)

===0===
*@-party

===A===
*abbrev
*amper
*anti-idiotarianism

===B===
*bonk/oif
*Bzzzt! Wrong.

===C===
*C|N>K

----
*[[null device|dev/null]]

I changed this to /dev/null which works -- although we can't remove the redirect (called by two other pages) this does make a little more sense since the direct link does work.

I hope... I'm going to test this before I make any real changes I don't know how to reverse.

If I was wrong to change this, replace what I currently put there with the text.

[[User:Frob23|Frob23]] 18:28, Jan 21, 2005 (EST)

Talk:List of Jargon File Entries

2005-01-21T23:24:40Z

Frob23:

Please put deleted entries here, so if anybody disagrees, they can put them back in. [[User:Crazyeddie|Crazyeddie]] 18:12, Jul 14, 2004 (EDT)

===0===
*@-party

===A===
*abbrev
*amper
*anti-idiotarianism

===B===
*bonk/oif
*Bzzzt! Wrong.

===C===
*C|N>K

----
*[[null device|dev/null]]

I changed this to /dev/null which works and we should now be able to remove the unnecessary redirect.

I hope... I'm going to test this before I make any real changes I don't know how to reverse.

[[User:Frob23|Frob23]] 18:23, Jan 21, 2005 (EST)

Talk:List of Jargon File Entries

2005-01-21T23:23:50Z

Frob23:

Please put deleted entries here, so if anybody disagrees, they can put them back in. [[User:Crazyeddie|Crazyeddie]] 18:12, Jul 14, 2004 (EDT)

===0===
*@-party

===A===
*abbrev
*amper
*anti-idiotarianism

===B===
*bonk/oif
*Bzzzt! Wrong.

===C===
*C|N>K

----
*[[null device|dev/null]]

I changed this to *[[/dev/null]] which works and we should now be able to remove the unnecessary redirect.

I hope... I'm going to test this before I make any real changes I don't know how to reverse.

[[User:Frob23|Frob23]] 18:23, Jan 21, 2005 (EST)

Talk:List of Jargon File Entries

2005-01-21T23:20:51Z

Frob23:

Please put deleted entries here, so if anybody disagrees, they can put them back in. [[User:Crazyeddie|Crazyeddie]] 18:12, Jul 14, 2004 (EDT)

===0===
*@-party

===A===
*abbrev
*amper
*anti-idiotarianism

===B===
*bonk/oif
*Bzzzt! Wrong.

===C===
*C|N>K

----
*[[null device|dev/null]]

I changed this to [[//dev/null]] which works and we should now be able to remove the unnecessary redirect.

I hope... I'm going to test this before I make any real changes I don't know how to reverse.

User talk:Frob23

2005-01-21T23:14:48Z

Frob23:

User:Frob23

2005-01-21T23:07:06Z

Frob23:

User talk:Frob23

2005-01-21T23:04:12Z

Frob23:

User talk:Frob23

2005-01-21T22:01:45Z

Frob23:

User:Frob23

2005-01-21T03:34:03Z

Frob23:

User:Frob23

2005-01-21T03:33:37Z

Frob23:

=frob23=

Often known in real life and in virtual life as Eric Fenderson, although neither of those are included in his actual given name. Eric Fenderson is obsessed with Unix in all its forms. He swears each night before falling off to sleep that he will, one day, port V7 to modern hardware.

[[Frob]] is an action of mindless fiddling with something (usually physical). This is the root word from which I take my user-name. I've used it for a long, long time mainly because a lot of my computer activities were mindless fiddling. Stuff like adding a password to command.com or changing the commands DOS used. Mindless stuff which I continued to do when I moved on to real operating systems. The wonderful thing about frobbing is that often you learn a lot by playing around without intending to learn anything from it.

I spent three years working towards a computer engineering major before I realized that it was not for me. Surprisingly (to myself at the time) my experience with Linux benefited me in that major because all of the work was done on *nix machines. I found [[FreeBSD]] during that time and have been using it steadily ever since but I still have an affection for Linux... she was my first.

I like the wiki and would add more but most of the areas where I could add information would be in the Jargon definitions. And, as it has been pointed out, it is important to not allow them to overwhelm the real information this wiki contains. There are good online sources for the Jargon file.

I have been obsessed with [[Hacker]] [[jargon]] and information ever since I found a hard copy of The New Hacker's Dictionary (version 1) at a local library. This was many years ago but I remember it gave me a vision of something deeper in the mindless tooling around with computers I was doing. I have since obtained hard copies of it and the two subsequent versions for myself. And, when the library moved across town, I was even able to purchase the worn original for $4.00 from the library because they were going to throw it out.

Almost accidentally, I have found myself fitting the description of a Hacker from the appendix. Right down to being a Theater Technician -- which at the time was something I decided to do to avoid the stereotype I saw myself fitting.

So, anyway, clearly I would love to share the source with those who are coming behind and don't know the joy. When I first heard the [[-p convention]] in real life it brought a smile to my face. It made me realize that I am part of a tradition that came before me and will go on beyond me. I want to share that with others.

Well, that's a rambling user page.

--[[User:Frob23|Frob23]] 22:26, Jan 20, 2005 (EST)