explain xkcd - User contributions [en]

376: Bug

2016-07-17T19:39:18Z

Alexbuzzbee: Add 'maximum' age for 2016

{{comic
| number = 376
| date = January 28, 2008
| title = Bug
| image = bug.png
| titletext = The universe started in 1970. Anyone claiming to be over 38 is lying about their age.
}}

==Explanation==
In computer systems, time is measured starting from some arbitrarily chosen point. That particular time is known as the "{{w|Unix time|epoch}}" for that system. The {{w|UNIX}} operating system internally uses an epoch of January 1, 1970, and measures the time as a number of seconds from then. Since this was intended only for things internal to the OS (File last modified times and the like), using 1-Jan-1970 was safe as no UNIX systems existed before that date. Dates before 1 January, 1970 are represented by negative values.

Commonly known as the {{w|year 2038 problem}}, at 03:14:08 on 19 January 2038, the 32-bit versions of the Unix time stamp will cease to work, as it will overflow the largest value that can be held in a signed 32-bit number. The 64-bit version "will" expire at 15:30:08 on 4 December 292,277,026,596.

[[Cueball]] has clearly misused the system date in some way, his friend makes a pun by combining "Epoch" with "Epic Fail" - a colloquial term meaning "a very big mistake was made".

The title text takes the joke to the next level, claiming that the entire universe began when Unix did, and therefore no one can be older than 38 (at the time of the comic; now 46 as of 2016 (the formula is 30 + (current year - 2000) (actually current year - 1970 but it's easier to remember like this))), which would explain away the bug since no earlier dates would be needed. This is also similar to {{w|Last Thursdayism}}.

==Transcript==
:[Cueball sits at a computer, staring at the screen and rubbing his chin in thought. A friend stands behind him.]
:Cueball: Weird — My code's crashing when given pre-1970 dates.
:Friend [pointing at the computer]: Epoch fail!

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Computers]]
[[Category:Programming]]
[[Category:Puns]]

1703: Juno

2016-07-06T15:34:42Z

Alexbuzzbee: Added initial draft of explanation.

{{comic
| number = 1703
| date = July 6, 2016
| title = Juno
| image = juno.png
| titletext = "The name wasn't a tip-off?" "Honestly, at first I thought you were saying 'Juneau'. A gravity assist seemed like a weird way to get to Alaska, but I figured it must be more efficient or something."
}}

==Explanation==
{{incomplete|Just a first draft.}}

Speaking for NASA, a character (not Ponytail?) announces that Juno has arrived at Jupiter within one second of its scheduled arrival. The joke is that Juno was meant to arrive at Saturn, but the timing is still apparently the same.

In the title text, it is revealed that yet another character believed Juno was destined for Alaska.

==Transcript==
:[Blonde] After traveling 1.7 billion miles, the Juno spacecraft reached Jupiter within one second of its scheduled arrival time.

:[Off] Very impressive!

:[Blonde] Thank you.

:[Megan] I mean, we were aiming for Saturn. Still, nailed the time.

:[Blonde] Shhhh.

{{comic discussion}}

Talk:501: Faust 2.0

2016-03-21T04:18:17Z

Alexbuzzbee:

It's also a reference to cd sleeve seals that say "by tearing this seal you agree to the enclosed license agreement" as it is obvious that mephistopheles has already entered the room [[Special:Contributions/173.245.53.163|173.245.53.163]] 18:19, 25 March 2014 (UTC)
:What if I cut around the seal? --[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 04:14, 21 March 2016 (UTC)

630: Time Travel

2016-03-21T04:17:25Z

Alexbuzzbee: /* Transcript */

{{comic
| number = 630
| date = August 31, 2009
| title = Time Travel
| image = time travel.png
| titletext = She also starts every letter with "Dear Future <your name>"
}}

==Explanation==
[[Megan]] prefaces her statements with "I've traveled here from the year 1983 [likely the year of her birth] to say this." The statement is (assuming 1983 to be her birthday or, at least, a year she lived during) perfectly valid, albeit not very meaningful and gives more emphasis on what she is about to say, only to say something quite anticlimactic and mundane.

[[Cueball]] notes this but still wishes that she would stop saying that as it is superfluous and captures more attention than her statement is actually worth. It would also get annoying to hear that same line repeated numerous times.

The title text continues this idea of Megan inserting another superfluous - although true - forwards to her letters, which would also likely become annoying.

==Transcript==
:Megan: I've traveled here from the year 1983 to say this:
:Megan: ''Are there any bagels left?''
:[Cueball is eating something (possibly a bagel?).]
:While it's technically true, I wish she'd stop prefacing every sentence with that.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Time travel]]

Talk:630: Time Travel

2016-03-21T04:16:33Z

Alexbuzzbee:

Dear Future Husband...better toast it right. [[User:Elvenivle|Elvenivle]] ([[User talk:Elvenivle|talk]])

I believe Cueball is in fact eating a bagel. --[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 04:16, 21 March 2016 (UTC)

Talk:501: Faust 2.0

2016-03-21T04:14:32Z

Alexbuzzbee:

It's also a reference to cd sleeve seals that say "by tearing this seal you agree to the enclosed license agreement" as it is obvious that mephistopheles has already entered the room [[Special:Contributions/173.245.53.163|173.245.53.163]] 18:19, 25 March 2014 (UTC)
What if I cut around the seal? --[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 04:14, 21 March 2016 (UTC)

Talk:501: Faust 2.0

2016-03-21T04:13:58Z

Alexbuzzbee:

It's also a reference to cd sleeve seals that say "by tearing this seal you agree to the enclosed license agreement" as it is obvious that mephistopheles has already entered the room [[Special:Contributions/173.245.53.163|173.245.53.163]] 18:19, 25 March 2014 (UTC)
What if I cut around the seal? --[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 04:13, 21 March 2016 (UTC)

Talk:1653: United States Map

2016-03-09T23:39:18Z

Alexbuzzbee:

But what prompted this map? Has there been a real life event that influenced Randall to create this?
[[Special:Contributions/141.101.91.25|141.101.91.25]] 07:32, 9 March 2016 (UTC)

Yes, this is about voting districts. They are so random you can not guess where your vote will count: https://www.youtube.com/watch?v=90RajY2nrgk

08:10, 9 March 2016 (UTC)

(Finally, someone made the page so I can post this. :| )

I removed the names from Randall's map! [http://i.imgur.com/Mvi8j9s.jpg Here's a blank version!] Muahahaha! [[User:Quoice|Quoice]] ([[User talk:Quoice|talk]]) 07:39, 9 March 2016 (UTC)
:Cool. Could you be so mean as to make a version including the shapes of Alaska and Hawaii. You could use the ones from Randall's map of United shapes as templates. That would be fantastic! --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:03, 9 March 2016 (UTC)

Maybe add a table with every state cut out; and add a correct map with the cut out pieces in the right place? [[User:SirKitKat|sirKitKat]] ([[User talk:SirKitKat|talk]]) 09:05, 9 March 2016 (UTC)
:That would just be a normal map... The piece could go over a real map in the wrong place to show it. Or rather the entire map should be overlaid on a real map... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:22, 9 March 2016 (UTC)
::This sounds like a great idea to me! Case of "A picture is worth a thousand words". [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 11:39, 9 March 2016 (UTC)

First thing that comes to mind when I look at the map is seeing New York being against the Mexico border. I wonder how New Yorkers would deal with the Mexicans coming across. --[[Special:Contributions/173.245.54.28|173.245.54.28]] 14:43, 9 March 2016 (UTC)

This proves it: continental drift is real, and much faster than we thought. [[Special:Contributions/162.158.114.217|162.158.114.217]] 15:18, 9 March 2016 (UTC)

[[File:1653-rearranged.png]] -- [[User:Frankie|Frankie]] ([[User talk:Frankie|talk]]) 15:31, 9 March 2016 (UTC)
:AZ <-> NM [[Special:Contributions/162.158.56.173|162.158.56.173]] 16:38, 9 March 2016 (UTC)
:RI should be rotated [[User:Azsr|Azsr]] ([[User talk:Azsr|talk]]) 17:31, 9 March 2016 (UTC)
:: D'oh! Fixed AZ & NM (although server is still caching the original). Leaving RI as is due to caption arrangement. -- [[User:Frankie|Frankie]] ([[User talk:Frankie|talk]]) 18:00, 9 March 2016 (UTC)
:::Great map. Have linked from the explanation at the top. Also made my own real life jigsaw which I put in the trivia.

There's nothing in the article right now that indicates the shapes of the states have been altered slightly so that they fit together seamlessly in this arrangement. I think that's an important point. [[Special:Contributions/162.158.255.80|162.158.255.80]] 15:53, 9 March 2016 (UTC)
:I think that's obvious [[Special:Contributions/141.101.70.157|141.101.70.157]] 16:18, 9 March 2016 (UTC)
::I mentioned it in the trivia. Maybe it should go up also? But it is surprisingly close to being correct within the reasonable limits of the resolution --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 19:44, 9 March 2016 (UTC)

What happened to Long Island (part of NY)?{{unsigned ip|108.162.218.118}}

The article indicates Maine has only been moved, but it's also been rotated 180 degrees. (Upside down) {{unsigned ip|198.41.235.107}}
:I will correct my mistake then ;-) --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 19:44, 9 March 2016 (UTC)

So glad I'm not in Illinois any more... I guess I'm in Texas now. [[Special:Contributions/108.162.221.18|108.162.221.18]] 18:04, 9 March 2016 (UTC)

<nowiki>*</nowiki> Do not use for navigation. [[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 23:39, 9 March 2016 (UTC)

288: Elevator

2015-12-08T02:52:42Z

Alexbuzzbee: /* Explanation */ Added the exclamation mark from the slip.

{{comic
| number = 288
| date = July 11, 2007
| title = Elevator
| image = Elevator.jpg
| titletext = Quick, try it with 'LOVE'.
}}

==Explanation==
[[Cueball]] is in an elevator, and notices that, beneath the certificate of [[Elevator Inspection]], mandatory in all U.S. elevators at least, there are buttons for Floor 1, 2, 3, and 4, and then a mysterious unlabeled button. Possible logical conclusions he might have made include (1) there is a fifth floor reachable by pushing the bottom button which for some reason is not labeled; or (2) the button has some other function, a common one is to stop the elevator wherever it may be; or (3) the panel with the buttons is from a template used for various elevators with up to five floors, and as this particular elevator only goes to four floors the bottom button is unlabeled and nothing will happen if he pushes it.

He has, however, chosen to accept a different explanation: the fifth button is not currently assigned, but giving it a label will assign it to whatever floor or other function he can give it. The possibilities are truly endless. And so, the intrepid Cueball writes "Zeppelin!" on a slip of paper, tapes it next to the unassigned button, thereby assigning it to move the elevator not to Floor 5 but to a {{w|Zeppelin}}. And it works – the elevator opens aboard a Zeppelin floating in the air, high above a land with many lakes.

The title text is most likely a reference to the Aerosmith song "Love in an Elevator," which really is about sex in an elevator. However, it would also be great if one could reach the elevation of love by getting there in a magic elevator.

==Transcript==
:[Elevator panel, with a Certificate of Inspection and five floor buttons, numbered 1–4. The fifth button is unlabeled.]
:[Cueball thinks.]
:[Cueball writes something on a small piece of paper.]
:''Write Write''
:[Cueball tapes it onto the panel.]
:[Elevator panel, with the same Certificate and buttons, and with the piece of paper labeling the fifth button "Zeppelin".]
:[Cueball presses the new "Zeppelin" button.]
:[Elevator moves.]
:Elevator: ''Ding''
:[Cueball is looking out the door of a Zeppelin. The Zeppelin is flying over a green landscape with many lakes.]

==Trivia==

*There is a [https://youtu.be/z9U9MN7_jus fan made animated version of this comic].

{{Comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics with color]]
[[Category:Airships]]
[[Category:Elevators]]

Talk:149: Sandwich

2015-08-23T02:51:33Z

Alexbuzzbee: REALLY fix my comment

Note that it is more effective to write "sudo !!" to redo the last command but with sudo added to it. {{unsigned|Agge.se}}

:Using <code>sudo !!</code> outputs the previous command with sudo into your bash (other shells as well) history, so to bash what you said was "sudo make me a sandwich" not "sudo !!". [[User:Lcarsos|lcarsos]] ([[User talk:Lcarsos|talk]]) 16:46, 29 October 2012 (UTC)

<code>sudo</code> requires '''user''' password, not admin password, but you need to be in <code>sudoers</code> file. --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 12:14, 15 December 2012 (UTC)

:How many people will know the difference? In a typical Ubuntu-family install with only one human user, root doesn't ''have'' a password, but the one user who does is a sudoer (and has to use <code>sudo</code> or <code>su</code> to act as root, rather than doing so starting at login). [[User:Promethean|Promethean]] ([[User talk:Promethean|talk]]) 06:08, 30 August 2013 (UTC)

"the user first must type their password" This is not accurate. It is the default, but many domains disable that requirement.
[[Special:Contributions/173.245.52.92|173.245.52.92]] 06:47, 14 January 2015 (UTC)

I believe the original comic actually read "Sudo bang bang" instead of "Sudo make me a sandwich". Here's a link to what I think is a copy of the [http://stackoverflow.com/questions/15137461/what-is-sudo-bang-bang original]. I'm not sure which of the two is actually the original. {{unsigned ip|‎99.95.158.248}}
:The words "bang bang" (particularly the first B) look a bit fuzzy/pixelated compared to the rest of the text, which gives me the feeling that it was edited from this one, which is the original. [[User:Zowayix|Zowayix]] ([[User talk:Zowayix|talk]]) 23:03, 23 January 2014 (UTC)
::If you click on the image (on the Stack Overflow link), it leads you to http://justinsomnia.org/2006/09/sudo-bang-bang/, which says: 'This just occurred to me' [comic] 'Original comic from xkcd by Randall Munroe', implying it was indeed edited. [[Special:Contributions/141.101.99.14|141.101.99.14]] 20:42, 11 August 2014 (UTC)

Comment: This conversation is an easter egg in Google Now on Android tablet. Using voice search to say "make me a sandwich" will give the reply "what? make it yourself", adding "sudo" will get the response "ok". I assume the Google now implementation came later and is based on xkcd. {{unsigned ip|141.101.99.27}}

This reworked for the Make utility:
<code><pre>
$ make sandwich
Must be root
$ sudo make sandwich
cc sandwich
mv sandwich /etc/sandwich
sandwich installed in /etc
$ _
</pre></code>
[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 02:50, 23 August 2015 (UTC)

Talk:149: Sandwich

2015-08-23T02:50:59Z

Alexbuzzbee: Fix my comment

Note that it is more effective to write "sudo !!" to redo the last command but with sudo added to it. {{unsigned|Agge.se}}

:Using <code>sudo !!</code> outputs the previous command with sudo into your bash (other shells as well) history, so to bash what you said was "sudo make me a sandwich" not "sudo !!". [[User:Lcarsos|lcarsos]] ([[User talk:Lcarsos|talk]]) 16:46, 29 October 2012 (UTC)

<code>sudo</code> requires '''user''' password, not admin password, but you need to be in <code>sudoers</code> file. --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 12:14, 15 December 2012 (UTC)

:How many people will know the difference? In a typical Ubuntu-family install with only one human user, root doesn't ''have'' a password, but the one user who does is a sudoer (and has to use <code>sudo</code> or <code>su</code> to act as root, rather than doing so starting at login). [[User:Promethean|Promethean]] ([[User talk:Promethean|talk]]) 06:08, 30 August 2013 (UTC)

"the user first must type their password" This is not accurate. It is the default, but many domains disable that requirement.
[[Special:Contributions/173.245.52.92|173.245.52.92]] 06:47, 14 January 2015 (UTC)

I believe the original comic actually read "Sudo bang bang" instead of "Sudo make me a sandwich". Here's a link to what I think is a copy of the [http://stackoverflow.com/questions/15137461/what-is-sudo-bang-bang original]. I'm not sure which of the two is actually the original. {{unsigned ip|‎99.95.158.248}}
:The words "bang bang" (particularly the first B) look a bit fuzzy/pixelated compared to the rest of the text, which gives me the feeling that it was edited from this one, which is the original. [[User:Zowayix|Zowayix]] ([[User talk:Zowayix|talk]]) 23:03, 23 January 2014 (UTC)
::If you click on the image (on the Stack Overflow link), it leads you to http://justinsomnia.org/2006/09/sudo-bang-bang/, which says: 'This just occurred to me' [comic] 'Original comic from xkcd by Randall Munroe', implying it was indeed edited. [[Special:Contributions/141.101.99.14|141.101.99.14]] 20:42, 11 August 2014 (UTC)

Comment: This conversation is an easter egg in Google Now on Android tablet. Using voice search to say "make me a sandwich" will give the reply "what? make it yourself", adding "sudo" will get the response "ok". I assume the Google now implementation came later and is based on xkcd. {{unsigned ip|141.101.99.27}}

This reworked for the Make utility:
<code>
$ make sandwich
Must be root
$ sudo make sandwich
cc sandwich
mv sandwich /etc/sandwich
sandwich installed in /etc
$ _
</code>
[[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 02:50, 23 August 2015 (UTC)

Talk:149: Sandwich

2015-08-23T02:50:20Z

Alexbuzzbee: Add a comment

Note that it is more effective to write "sudo !!" to redo the last command but with sudo added to it. {{unsigned|Agge.se}}

:Using <code>sudo !!</code> outputs the previous command with sudo into your bash (other shells as well) history, so to bash what you said was "sudo make me a sandwich" not "sudo !!". [[User:Lcarsos|lcarsos]] ([[User talk:Lcarsos|talk]]) 16:46, 29 October 2012 (UTC)

<code>sudo</code> requires '''user''' password, not admin password, but you need to be in <code>sudoers</code> file. --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 12:14, 15 December 2012 (UTC)

:How many people will know the difference? In a typical Ubuntu-family install with only one human user, root doesn't ''have'' a password, but the one user who does is a sudoer (and has to use <code>sudo</code> or <code>su</code> to act as root, rather than doing so starting at login). [[User:Promethean|Promethean]] ([[User talk:Promethean|talk]]) 06:08, 30 August 2013 (UTC)

"the user first must type their password" This is not accurate. It is the default, but many domains disable that requirement.
[[Special:Contributions/173.245.52.92|173.245.52.92]] 06:47, 14 January 2015 (UTC)

I believe the original comic actually read "Sudo bang bang" instead of "Sudo make me a sandwich". Here's a link to what I think is a copy of the [http://stackoverflow.com/questions/15137461/what-is-sudo-bang-bang original]. I'm not sure which of the two is actually the original. {{unsigned ip|‎99.95.158.248}}
:The words "bang bang" (particularly the first B) look a bit fuzzy/pixelated compared to the rest of the text, which gives me the feeling that it was edited from this one, which is the original. [[User:Zowayix|Zowayix]] ([[User talk:Zowayix|talk]]) 23:03, 23 January 2014 (UTC)
::If you click on the image (on the Stack Overflow link), it leads you to http://justinsomnia.org/2006/09/sudo-bang-bang/, which says: 'This just occurred to me' [comic] 'Original comic from xkcd by Randall Munroe', implying it was indeed edited. [[Special:Contributions/141.101.99.14|141.101.99.14]] 20:42, 11 August 2014 (UTC)

Comment: This conversation is an easter egg in Google Now on Android tablet. Using voice search to say "make me a sandwich" will give the reply "what? make it yourself", adding "sudo" will get the response "ok". I assume the Google now implementation came later and is based on xkcd. {{unsigned ip|141.101.99.27}}

This reworked for the Make utility:
$ make sandwich
Must be root
$ sudo make sandwich
cc sandwich
mv sandwich /etc/sandwich
sandwich installed in /etc
$ _

234: Escape Artist

2015-03-30T13:08:09Z

Alexbuzzbee: /* Explanation */ Grammar.

{{comic
| number = 234
| date = March 12, 2007
| title = Escape Artist
| image = escape_artist.png
| titletext = Easier to escape: n-layered nested quotes or an iron maiden?
}}

==Explanation==
{{w|Harry Houdini}} (born Erik Weisz/Ehrich Weiss) was a famous escape artist, whose more famous routines included escaping straitjackets and switching places with an assistant while locked inside a box.

The word "escape" also has a meaning {{w|Escape character|in computer science}}. To "escape" something in programming means to input some "escape character" to force to the computer to use a different interpretation of the following character (e.g. letter, number, or symbol). The escape character in most interpreters or languages is the backslash (\), and it's usually used to suppress the special meaning of the following symbol. For example, in most programming languages, strings are specified in quotation marks (e.g. "this is a string"). In this case, if the programmer tried to put a quotation mark inside the string, the compiler would interpret it as the end of the string, and probably end up having an error when it sees the rest of the string. Because of this, most languages also specify that \" can be used to literally just be a quotation mark, which allows programmers to put actual quotation mark characters into strings.

The problem [[Cueball]] is having is related to the fact that {{w|Bash (Unix shell)|the Bash shell}} interprets spaces as a special syntactic marker, when he actually just wants the spaces to be literal space characters. In this case, escaping the spaces with \ would force Bash to interpret his script in this way.

(There is one other way the escape character is sometimes used, but we'll ignore it for the sake of explaining the comic.)

The person talking to Cueball is having a separate conversation about Houdini as Cueball thinks aloud about his script issue, which results in diverging conversations. This eventually leads Cueball to suggest that Houdini might have "escaped" (freed himself from) handcuffs by "escaping" (removing the special meaning from) them with backslashes.

Sometimes, escape characters need to be "nested" - the backslash character itself can be escaped as \\ to produce a literal backslash, so if, for example, one needs to produce a literal quotation mark to output to a script file, and that script file ''also'' needs to have the quotation mark escaped, one would need to type it out as \\\", which would be output as \". If I needed to actually output that \\\", one would need to type it as \\\\\\\". The number of backslashes needed grows, and can be very hard to keep track of. This behavior is a type of n-level nested quotation mentioned in the title text.

An {{w|iron maiden (torture device)|iron maiden}} is supposedly a medieval torture device, currently believed to have been invented for tourism purposes much later than the time period when it was said to have been used.
Harry Houdini's escapes include an escape from a purported "iron maiden," although it only vaguely resembles the "medieval" torture device.

==Transcript==
:[Cueball sits before a computer on a desk while another man stands behind him.]
:Man: I was fascinated by locks as a kid. I loved how they turned information and patterns into physical strength.
:Cueball: Why does my script keep dying?

:[Closeup on Cueball sitting at the computer.]
:Man: And a lock invites you to try and open it. It's the hacker instinct. Only your ignorance stands in the way.
:Cueball: Wait it's passing bad strings.

:[Returns to the two shot of both men.]
:Man: I admired Harry Houdini, how he could open any lock and free himself from any restraint.
:Cueball: Ah - Bash is parsing the spaces.

:Man: Sure some of it was fakery and showmanship. But I still wonder how he so consistently escaped handcuffs.
:Cueball: Backslashes?
:Man: Huh?
:Cueball: Never mind.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Programming]]

379: Forgetting

2015-03-30T13:01:21Z

Alexbuzzbee: /* Explanation */ Modified to a comment: probably PHP, not C++.

{{comic
| number = 379
| date = February 4, 2008
| title = Forgetting
| image = forgetting.png
| titletext = Of course, the assert doesn't work.
}}

==Explanation==
[[Cueball]] is writing a piece of code (probably in the programming language {{w|PHP}}) which removes an item from a data structure called a {{w|Linked list}} (the first two lines of the text). Then, he writes a {{w|Comment (computer programming)|comment}} (which is delimited by the double slashes) relating the code to his personal life. Finally, he adds an {{w|Assertion (computing)|assertion}}, which is normally a formal specification of a condition which should always be true (with which the programmer ensures that e.g. mass is not negative). But in this case, instead of asserting a software-related predicate, he asserts that "it's going to be okay" - and because of how {{w|String literal|string literals}} are treated by the interpreter, the assertion will be true.

An "assert" is a programming statement that allows you to insert sanity checks into your code. For example, if you were writing a program to calculate the speed of a neutrino, then at the end of the calculation you could say:
:<code>assert ( velocity_of_neutrino <= speed_of_light );</code>

If the assertion fails, then the program will stop with an error. This would be much better than publishing an embarrassing paper, for example.

The title text explains that assertion in question fails: we cannot be sure that things are going to be ok.

==Transcript==
:[Cueball sits at computer, coding.]
prev->next = toDelete->next;
delete toDelete;

//if only forgetting were
//this easy for me.

:Cueball: <sniff>

:[Cueball lowers his head into his hands and cries.]

:[Cueball types again.]
assert "It's going to be okay.";

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Programming]]

Talk:413: New Pet

2015-03-16T14:36:09Z

Alexbuzzbee:

Is anyone else tempted to do this for real? Because I certainly am. [[Special:Contributions/130.160.145.185|130.160.145.185]] 23:24, 9 March 2013 (UTC)

Even more possible now with the newer, smaller raspberry Pi computers. Someone PLEASE do it. {{unsigned ip|141.101.98.228}}
:NEW PROJECT. [[User:Alexbuzzbee|Alexbuzzbee]] ([[User talk:Alexbuzzbee|talk]]) 14:36, 16 March 2015 (UTC)

Here is the comments section on the xkcd site: http://blog.xkcd.com/2008/04/22/hooray-robots/#comments (Sorry. Don't know how to make it a link.) There are a number of proposed designs and several readers who claim to be making one. There are 248 entries so I only skimmed over them. [[User:ExternalMonolog|ExternalMonolog]] ([[User talk:ExternalMonolog|talk]]) 20:48, 21 January 2014 (UTC)ExternalMonolog

1192: Humming

2014-05-11T13:53:01Z

Alexbuzzbee: Made "Randall" a link, and fixed a spelling mistake.

{{comic
| number = 1192
| date = March 29, 2013
| title = Humming
| image = humming.png
| titletext = I'm so bad at carrying a tune, those 'find a song by humming its melody' websites throw an HTTP 406 error as soon as I start to hum.
}}

==Explanation==
Services like {{w|MusicBrainz}} and {{w|SoundHound}} can detect a recorded song's {{w|acoustic fingerprint}} and match it with an existing song. This lets them identify the title and artist of an unnamed recorded musical extract. In this comic, [[Megan]] hacks the acoustic fingerprint database to add her own entry with a message to [[Cueball]], in which she asks him to buy [[1022|cat food]].

HTTP error code 406 means Not Acceptable. When a client requests data from a server, the client lists the data formats that it can accept. If a server is unable to provide data in any format that the client accepts, the server returns error 406 Not Acceptable. For example, this can occur if a client requests XML but the server supports only JSON. In the comic, the standard meaning of the error message is ignored and the text "Not Acceptable" is taken literally: The server is offended by [[Randall]]'s humming.

==Transcript==
:[Megan is humming a tune.]
:Cueball: Hey.
:Cueball: What's that?
:[Megan is still humming the same tune.]
:Cueball: What are you humming?
:Cueball: Should I know the tune?
:Cueball: ...Hmm...
:[Cueball gets out his phone and opens up a music recognition program.]
:Phone: Identify song
:Phone: Recorded
:Phone: > Live [beta]
:Phone: Identifying...
:[A zoom in on the phone screen. An album cover with a picture of Megan on it.]
:Positive match:
:''Check it out!''
:By I hacked the audio fingerprint database
:Feat. MEEEEEE
:Track: We're out of cat food (pick some up?)

==Trivia==
*[[1199: Silence]] further explores song identification.
*[[1022: So It Has Come To This]] is also about running out of Cat Food.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Music]]

1192: Humming

2014-05-11T13:48:50Z

Alexbuzzbee: Changed "The Author" to "Randal"

{{comic
| number = 1192
| date = March 29, 2013
| title = Humming
| image = humming.png
| titletext = I'm so bad at carrying a tune, those 'find a song by humming its melody' websites throw an HTTP 406 error as soon as I start to hum.
}}

==Explanation==
Services like {{w|MusicBrainz}} and {{w|SoundHound}} can detect a recorded song's {{w|acoustic fingerprint}} and match it with an existing song. This lets them identify the title and artist of an unnamed recorded musical extract. In this comic, [[Megan]] hacks the acoustic fingerprint database to add her own entry with a message to [[Cueball]], in which she asks him to buy [[1022|cat food]].

HTTP error code 406 means Not Acceptable. When a client requests data from a server, the client lists the data formats that it can accept. If a server is unable to provide data in any format that the client accepts, the server returns error 406 Not Acceptable. For example, this can occur if a client requests XML but the server supports only JSON. In the comic, the standard meaning of the error message is ignored and the text "Not Acceptable" is taken literally: The server is offended by Randal's humming.

==Transcript==
:[Megan is humming a tune.]
:Cueball: Hey.
:Cueball: What's that?
:[Megan is still humming the same tune.]
:Cueball: What are you humming?
:Cueball: Should I know the tune?
:Cueball: ...Hmm...
:[Cueball gets out his phone and opens up a music recognition program.]
:Phone: Identify song
:Phone: Recorded
:Phone: > Live [beta]
:Phone: Identifying...
:[A zoom in on the phone screen. An album cover with a picture of Megan on it.]
:Positive match:
:''Check it out!''
:By I hacked the audio fingerprint database
:Feat. MEEEEEE
:Track: We're out of cat food (pick some up?)

==Trivia==
*[[1199: Silence]] further explores song identification.
*[[1022: So It Has Come To This]] is also about running out of Cat Food.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Music]]