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March 23

noise jitter effects

can ground loops over usb induce jitter — Preceding unsigned comment added by 77.35.48.216 (talk) 03:31, 23 March 2013 (UTC)

If you mean monitor jitter, I guess it's not inconceivable, but it seems very unlikely. (Presuming you have a CRT monitor. If it's LCD, no chance at all.) Looie496 (talk) 05:06, 23 March 2013 (UTC)

change movie speed in vlc media player does not work

when i play a movie ,and in vlc media player it runs faster,when i try to change its speed using playback-speed-normal,it does not work, how can i fix it.i m using windows xp — Preceding unsigned comment added by 182.187.51.160 (talk) 05:23, 23 March 2013 (UTC)

The VideoLan guys (who make VLC) have a very explicit mechanism for reporting bugs. They are crotchety folks, because they have received spammy, misspelled, and uncapitalized reports for many years; if you expect them to volunteer time, spend some time reading how to report a bug. Nimur (talk) 17:02, 23 March 2013 (UTC)

Chrome

Every time I fire up Google Chrome, a few webpages like http://websearch.just-browse.info/ and (for some weird unknown reason) not one, but two tabs of google.com open up by default. I want a way to switch off the default sites that chrome accesses when I run it. Can anyone tell me exactly where to go and tweak what so I can see the startup sites and turn them off? (Much like turning off unneccessary start-up programs when switching on your computer) 14.96.97.124 (talk) 15:58, 23 March 2013 (UTC)

Moved from Misc desk. Tevildo (talk) 16:40, 23 March 2013 (UTC)

You could tyep in the address bar: “chrome://settings/” and there, in the “on startup” section select the “Continue where I left off” option — Preceding unsigned comment added by Iskander HFC (talk • contribs) 19:50, 23 March 2013 (UTC)

All that stuff without the quotesIskánder Vigoa Pérez (talk) 19:52, 23 March 2013 (UTC)

Thanks. That totally worked. Except now when I start it, the new tab page opens, although it's set to "open a set of pages" and the set of pages contains only google.com's address (google's my homepage). Any way to fix this little bug? Everything else is fine otherwise. 14.99.179.58 (talk) 20:49, 23 March 2013 (UTC)

RPC-1 firmware or RPC-2 firmware?

How in general can one determine whether one has RPC-1 firmware or RPC-2 firmware?

I am specifically curious about a Mac G4 Powerbook from 2005 and a Gateway NV78 Laptop from 2009. Thanks. μηδείς (talk) 20:28, 23 March 2013 (UTC)

This site has a nice bit of information, and suggests using driveinfo to determine your drive's firmware. I can't vouch for the program's ability, nor do I know whether it works on a Mac. - Cucumber Mike (talk) 21:01, 23 March 2013 (UTC)

I think all drives manufactured starting in 2000 are RPC-2 unless you reflash them (see e.g. [1]). If you're interested in reflashing, note that free-software players like VLC will play discs from any region even on an RPC-2 drive, and commercial players will enforce a region even on RPC-1 drives by some software mechanism that may be difficult to circumvent. -- BenRG (talk) 23:27, 23 March 2013 (UTC)

March 24

File system type (Linux) displayed differently by various programs

Resolved

I'm adding a 3 Tb disk to my Linux box. Doing so by using the GNOME Disks utility (aka Palimpsest), resulted in the following error message: "The partition is misaligned by 512 bytes. This may result in very poor performance. Repartitioning is suggested.", without any obvious hints as to how to fix the error. Googling the message produced lots of hits, but no solutions that worked. After spending some hours fiddling with the disk utility + parted + gparted, I moved the disk to my Win7 box, created a 3Tb ntfs partition with diskmgmt.msc, and put the disk back into my Linux box. It now showed up fine in the disk utility, no complaints about errors. I was also able to mount it, without errors.

I then wanted to "convert" (destructively, I know) the /dev/sdb1 partition into an ext4 partition, by entering

sudo mkfs.ext4 /dev/sdb1

No errors in the disk utility. I can mount the disk, it the contents being as expected (only the lost+found directory). However, when I look at the disk setup with blkid, it shows up like so:

myname@mymachine:/mnt$ blkid
/dev/sda1: LABEL="Disk 1 (old Ub)" UUID="9b68bb9e-5cc4-4ab0-a21f-a607466cc2ee" TYPE="ext4" 
/dev/sda3: LABEL="Disk1 - xtra sp." UUID="f2327d30-3e90-4755-9149-7554f669c122" TYPE="ext4" 
/dev/sda4: LABEL="Disk 1 - Lubuntu" UUID="11c896f5-3e0b-44ea-ba20-6f67259e5b86" TYPE="ext4" 
/dev/sda5: UUID="f1b8a66f-916f-4bce-b674-243134373005" TYPE="swap" 
/dev/sdb1: LABEL="DiskWD1" UUID="9C44BB8444BB5FA6" TYPE="ntfs" 
/dev/sdc1: LABEL="Disk3 - 1.5 TB" UUID="4bbff5cb-3cfb-498a-a94b-46b75e36ba8c" TYPE="ext4" 
/dev/sdd1: LABEL="Disk2 - 1.5 TB" UUID="39588a06-9896-41b7-bba4-9c1e1beffdfc" TYPE="ext4" 

The problem is that /dev/sdb1 shows up as ntfs even though it actually is an ext4 partition. I'm not sure whether this is just an annoyance or a disaster waiting to happen. In either case I'd like to fix it before starting to use the disk. I know that cfdisk lets you set a "file system type identifying byte". I suspect this byte is the cause of the discrepancy, but cfdisk won't recognize the disk, which has a GUID Partition Table. Any suggestions on how to proceed? Thanks, --NorwegianBlue ^talk 11:42, 24 March 2013 (UTC)

Addendum: Here are the "file system type identifying bytes" as listed by cfdisk:

Extended content

01 FAT12 4F QNX4.x 3rd part A9 NetBSD 02 XENIX root 50 OnTrack DM AB Darwin boot 03 XENIX usr 51 OnTrack DM6 Aux1 AF HFS / HFS+ 04 FAT16 <32M 52 CP/M B7 BSDI fs 05 Extended 53 OnTrack DM6 Aux3 B8 BSDI swap 06 FAT16 54 OnTrackDM6 BB Boot Wizard hidden 07 HPFS/NTFS/exFAT 55 EZ-Drive BE Solaris boot 08 AIX 56 Golden Bow BF Solaris 09 AIX bootable 5C Priam Edisk C1 DRDOS/sec (FAT-12) 0A OS/2 Boot Manager 61 SpeedStor C4 DRDOS/sec (FAT-16 < 0B W95 FAT32 63 GNU HURD or SysV C6 DRDOS/sec (FAT-16) 0C W95 FAT32 (LBA) 64 Novell Netware 286 C7 Syrinx 0E W95 FAT16 (LBA) 65 Novell Netware 386 DA Non-FS data 0F W95 Ext'd (LBA) 70 DiskSecure Multi-Boo DB CP/M / CTOS / ... 10 OPUS 75 PC/IX DE Dell Utility 11 Hidden FAT12 80 Old Minix DF BootIt 12 Compaq diagnostics 81 Minix / old Linux E1 DOS access 14 Hidden FAT16 <32M 82 Linux swap / Solaris E3 DOS R/O

They're also listed in our article Partition type. --NorwegianBlue ^talk 12:22, 24 March 2013 (UTC)

Spelling out the details is a good way of solving a problem by oneself. I ran e2fsck. Problem disappeared. --NorwegianBlue ^talk 12:40, 24 March 2013 (UTC)

By default, gparted won't create misaligned partitions (the default is 1 Mib alignment), so I guess it was "helping" by keeping the alignment of whatever was on the disk before. In cases like this I generally nuke the partition table with dd and then run gparted to make a nice fresh one. -- Finlay McWalterჷTalk 13:25, 24 March 2013 (UTC)

Thanks, I'll try it! I still have 4 similar disks to go. I need to increase my storage space by a factor of ten, as I'm getting a ton of super 8 and analog video digitized. According to this link, I have to zero both the beginning and the end of the disk since it uses a GUID partition table. So I'll try it, using the linked howto for accessing the end of the disk. I'll dd-save the parts that I nuke, just to be on the safe side. Doing so has saved me more than once! --NorwegianBlue ^talk 21:43, 24 March 2013 (UTC)

Advanced Format might be relevant here. The default formatting on AF disks can result in a 512 byte misalignment and subsequent poor performance on Linux systems. Astronaut (talk) 23:45, 24 March 2013 (UTC)

Ok, here are my conclusions, for the benefit of anyone who might find this thread googling for the error messages:

• The misaligned disk problem affects both Seagate and Western Digital 3Tb disks. The only difference is that with the Western digital disk, the reported misalignment was 256 bytes. With the Seagate disk, the reported misalignment was 3072 bytes. The WD disk is described by the supplier as Western Digital® Desktop Green 3TB SATA 6Gb/s, (SATA 3.0), RPM = IntelliPower, 64MB Cache, 3.5 in., and has the producer ID WD30EZRX. The Seagate disk is described by the supplier as Seagate Barracuda® 3TB SATA 6Gb/s (SATA 3.0), 64MB Cache, 7200RPM, 3.5 in., and has the producer ID ST3000DM001. Both disks had 5860533168 blocks as reported by sudo cat /sys/block/sdd/size, which fits nicely with 3Tb and a block size of 512 bytes. The OS is Lubuntu 12.04.2 LTS.
• Zeroing the start and end of the disks, as suggested by Finlay, initially appeared to have no effect. Exactly the same error messages, with the same reported misalignments, were reported (still using palimpsest). I later checked to see whether the zeroing of the starts and ends of the disks had actually worked (by repeating the process, dd-ing the blocks to a file and doing hexdump -C). The supposedly zeroed beginnings and ends of the disk still contained data! I repeated the process, then did partprobe /dev/sdd (to tell the OS that the partition tables were changed) and rebooted. When I then checked whether the sectors were empty, they were. I then used gparted, created a GPT style partition table, and created one 3Tb ext4 partition. Everything went smoothly. When checking the disk with palimpsest, there was no warning of misalignment.
• Conclusion: Nuking the starts and ends of the disks as suggested by Finlay works, but you have to take care and check that the sectors are actually cleared, and that the OS is aware of it. I'm not sure why my initial attempts failed silently. Maybe I had palimpsest open, while dd-ing, and palimpsest locked the disk. Maybe I had actually succeeded in zeroing the sectors, but failed to tell the OS. I don't know. Anyway, it works now. --NorwegianBlue ^talk 15:58, 25 March 2013 (UTC)

It's very unlikely that any manufacturer would ship a drive with misaligned partitions, since it would kill their performance on benchmarks. Furthermore, a misalignment of 256 bytes is actually impossible, since it's not a multiple of the nominal sector size of 512 bytes. (The misalignment here is with the true sector size, which is probably 4096 bytes. These drives report 512-byte sectors for backward compatibility. If the true sector size is 512 bytes, the "misalignment" doesn't matter.) So I think this must be a bug in the software you're using. In any case, it does no harm to wipe the partition table and start over. -- BenRG (talk) 17:40, 25 March 2013 (UTC)

And even more unlikely that two manufacturers would. Googling "palimpsest misalignment bug" shows that it is a known bug. As far as I can figure out, it's a combination of an alignment bug and a misleading error message. --NorwegianBlue ^talk 18:46, 25 March 2013 (UTC)

You'd be surprised. I had an Seagate external (but USB3.0 so capable of reasonable performance) drive with misaligned partitions. I've heard of the same problem for people with other Seagate external drives of a similar kind. I'm guessing no one thought to update whatever tool they're using. I suspect WD must have done the same thing at some stage. Internal drives don't normally come formatted when purchased by themselves so no experience there. Nil Einne (talk) 20:54, 25 March 2013 (UTC)

There seem to be drives up to at least 3TB that still use 512-byte physical sectors, such as the Hitachi 7K3000. It's possible you had one of those and the tool you used didn't check for it before displaying the warning (perhaps because it was attached over USB). -- BenRG (talk) 03:51, 26 March 2013 (UTC)

No, other then the fact it is unlikely Seagate would want to use a drive made by their primary competitor (WD) for their external drives, in at least one case of someone I personally knew the external drive was disassembled to get at the internal drive and yes it was a Seagate drive (one of the newer 7200RPM ones that Seagate only makes now). Also various tool used such as Acronis alignment tool did claim the drive was an advanced format/4k drive although I didn't have a non 4k USB drive to test it worked properly on USB. (Incidentally even those with the offset jumper which AFAIK Seagate never used have a way of reporting this, at least for native ATA drives [2].) Nil Einne (talk) 20:05, 26 March 2013 (UTC)

ONCE AGAIN, Subscription feed layout on YouTube - how do I change it back?

The Subscription feed on YouTube changed its layout. I liked the old one better. How do I change it back?

The old layout showed its videos about 5 to a row, with titles under them. Very recently, it changed to show a layout that I don't appreciate as much because I see less previews on the same screenspace than in the old layout. That is why I want the old layout back, so how do I change it back? --70.179.161.230 (talk) 20:52, 24 March 2013 (UTC)

In general, you cannot force website publishers to provide the content that you want, in the format that you desire. Some website publishers allow you to configure the user-interface through preferences or settings; Youtube does not have such options. Some other website developers have the goodwill to provide simple, standardized content that makes it easy for you to customize the presentation - for example, you can re-layout an HTML document by applying your own stylesheet using a web browser. In practice, few websites publish their content as simple HTML documents, so it has become prohibitively difficult for end-users to modify the formatting and presentation of web content. Many new websites intentionally (ab)use the capabilities of hypertext, fixing the format so that the document is not even reflowable. This is particularly true for commercial websites whose developers intend to control your viewing experience. If you are unhappy with website publishers' formatting choices, you should contact the publisher directly - in this case, through their form-letter user feedback system, or simply avoid using their website. Nimur (talk) 04:56, 25 March 2013 (UTC)

Cell phone vibrations ?

I have a cell phone which has a vibrate setting. However, when I have it in my shirt pocket I occasionally feel it vibrate when nobody has called. This vibration seems shorter and less intense than an actual ring vibration.

1) Has anyone else noticed this ?

2) What could cause this ?

3) Could it be some type of sympathetic vibration caused by a noise in the environment ? StuRat (talk) 23:27, 24 March 2013 (UTC)

Other events might make your phone do this: An SMS message being received, for example, or maybe your phone detects the changes in signal strength and adjusts something like Facebook status accordingly. Astronaut (talk) 23:39, 24 March 2013 (UTC)

We should probably ask what sort of phone this is. Then again, I have two phones (Samsung Galaxy S2 and an iPhone 4 since you ask) and have also noticed this, but just put it down to ringxiety. (We really do HAAOE...) - Cucumber Mike (talk) 00:00, 25 March 2013 (UTC)

It's a Samsung S425G. I don't recall any previous phones doing this. StuRat (talk) 05:00, 25 March 2013 (UTC)

Sure it is your phone? Might be your heart trying to tell you something. I keep my vibrating phone in my trouser pocket, much more exciting!85.211.138.47 (talk) 11:47, 25 March 2013 (UTC)

• Our article is at Phantom_vibration_syndrome--in short, many people perceive this phenomenon. I believe there is some discussion of it in the scientific literature, but they might use slightly different terminology. Still, a few searches on Google Scholar will probably be rewarding. SemanticMantis (talk) 16:40, 25 March 2013 (UTC)

printer margins

Is there a place that tells what the margins are for various printers? Had I known that the HP 1000 has a minimum bottom margin of more than one inch, I would not have purchased it. (Such a large margin really messes things up, especially labels and pdfs.) Thank you.    → Michael J Ⓣ Ⓒ Ⓜ 23:51, 24 March 2013 (UTC)

You'd probably do best to download the owner's manual for the printer before you buy it. That should include such info under the specs section. StuRat (talk) 05:07, 25 March 2013 (UTC)

Most printers that fit on a desk will not print to the edges of paper. ¦ Reisio (talk) 21:40, 29 March 2013 (UTC)

March 25

Safari Extensions

These are a useful collection of extensions on my Safari page on my computer. Can I get these on my iPad? if so I cannot see how. Any ideas please? — Preceding unsigned comment added by 85.211.138.47 (talk) 11:07, 25 March 2013 (UTC)

As far as I know (or can tell) Safari extensions are not supported for iPad. --Mr.98 (talk) 20:17, 25 March 2013 (UTC)

Thanks, but that is a shame.85.211.138.47 (talk) 16:30, 28 March 2013 (UTC)

Where does Ubuntu store my installation files?

I've just installed The Battle for Wesnoth on my Ubuntu 12.10 32-bit PC, I do not know where the OS stores the game's music, sound effects, and saved gaming sessions. Please tell me where. Czech is Cyrillized (talk) 11:13, 25 March 2013 (UTC)

I don't know the game specifically, but most local files on linux systems are stored in your home directory, but they start with a ., which makes them hidden in most file managers. If you're in the shell use ls -a to see the . prefixed files. Shadowjams (talk) 11:37, 25 March 2013 (UTC)

I know Finlay answered already, but it's actually rare for installs to put themselves in your home directory. It's usually in /usr/share/, /usr/bin/, /etc/, and so forth. The . directories usually contain your saves and settings, which remains true in this case. --Wirbelwind(ヴィルヴェルヴィント) 22:01, 27 March 2013 (UTC)

The game is installed into /usr/share/games/wesnoth/1.10/

Specifically:

• Music: /usr/share/games/wesnoth/1.10/data/core/music/
• Sounds: /usr/share/games/wesnoth/1.10/sounds/ and /usr/share/games/wesnoth/1.10/data/core/sounds/

Save game files are kept in ~/.local/share/wesnoth/1.10/saves/

-- Finlay McWalterჷTalk 12:42, 25 March 2013 (UTC)

Bash comman history customization

Hello, I'd like to change the behavior of the "up arrow" key at the command prompt in Bash_(Unix_shell). In MATLAB, pressing "up" show all previous commands, one-by-one, with repeated presses (this is what my Bash on Ubuntu does by default). But, in Matlab, if you start to type in a command, e.g 'cd', then pressing "up" only cycles through previous commands that started with 'cd'. So- Can I do this in Bash? Can you help me with the appropriate code for configuration scripts? Thanks! SemanticMantis (talk) 16:29, 25 March 2013 (UTC)

Yes, see here. -- BenRG (talk) 17:28, 25 March 2013 (UTC)

Thanks! However, putting those lines in my .bashrc does not make the expected change. It does do something different with the bindings/history, but less - <up arrow> does not return "less foo", which is the most recent command in history starting with 'less'. SemanticMantis (talk) 17:57, 25 March 2013 (UTC)

Nevermind, for some reason it worked in my .inputrc, but not in .bashrc. I also ended up putting in the few extra lines here:[3]. SemanticMantis (talk) 18:05, 25 March 2013 (UTC)

Resolved

March 26

Google on Bing?

Can you Google on Bing? Do you still call it googling or do you call it binging? Bubba73 ^{You talkin' to me?} 04:48, 26 March 2013 (UTC)

Just as much as you can hoover with a goblin, or Tannoy an announcement with a Bose. -- Q Chris (talk) 14:15, 26 March 2013 (UTC)

Interesting comparison above. Generally, you'd just "search" Bing, as opposed to Binging Bing. -- Zanimum (talk) 13:18, 27 March 2013 (UTC)

Microsoft would have you "bing it" [4], or even "bing it on" [5]. But I don't see it happening. Also note the recent kerfluffle over "ogooglebar" [6]. Google would like to remind you that their name is their brand and trademark, and they have and will take steps to prevent genericisation. SemanticMantis (talk) 16:57, 27 March 2013 (UTC)

1950s IBM printer

1950s IBM printer

Can anyone identify this 1950s IBM printer? - Jmabel | Talk 06:01, 26 March 2013 (UTC)

That's not a printer. It's an accounting machine closely resembling the IBM 407, which was used as a component of a calculator system called an IBM CPC. You can see a picture of the whole system here -- note that on the right you can see a card punch that also appears in your picture. Looie496 (talk) 06:59, 26 March 2013 (UTC)

More specifically, it could be an IBM 402, 403, 412, or 418 -- they were all essentially identical in outward appearance, as shown on this page. Looie496 (talk) 06:59, 26 March 2013 (UTC)

• Thanks! - Jmabel | Talk 16:09, 26 March 2013 (UTC)

Value of null

In C, is it safe to assume that null will always compare as less than a valid pointer? I know it isn't safe to assume null==0. 173.52.95.244 (talk) 11:53, 26 March 2013 (UTC)

It is generally considred unsafe to compare pointers that aren't from the same allocation. The C specification doesn't seem to cover relational operators with null pointers, so you should consider the result of the comparision to be undefined and unsafe. It is safe to compare a pointer to 0 (as in if(p) or if(p==0)) to determine if it is null. This is because a 0 constant assigned to a pointer will be converted to a null pointer at compile time, regardless of the system's representation of a null pointer. See [7] for some discussion of null pointers, 5.3 is probably the most applicable question. 38.111.64.107 (talk) 13:18, 26 March 2013 (UTC)

yep sounds like mostly what I was going to say but that last edit beat me here. No the assumption is wrong. And comparing a pointer to zero is a valid test for null even if the actual value in a null pointer is not zero (but in practically all machines nowadays it is actually zero and thankfully C++ now has a nullptr to avoid that anyway) Most anything beyond that is machine dependent. See pointer_t and ptrdiff_t for the integer form of a pointer and for getting the difference between two pointers into the same array, they are mainly for getting the size of ther integer form right so a bit of low level work can be done on them. Otherwise one should normally avoid messing around with the contents of pointers. Dmcq (talk) 13:30, 26 March 2013 (UTC)

I have good reasons for messing with the contents of pointers! I think what Dmcq intends to say is that application logic rarely ought to directly modify object representation or allocation in memory; application logic should delegate that work to an abstraction of the memory system. Even if applications are implemented in a language that allows access to the memory representation (like C and C++), the application should let the system library or the program runtime environment handle the details.

On checking my copy of K&R, Section 5.4, I interpret the text to mean "NULL" is a convenience macro defined in stdio.h - and not a strict requirement of the language implementation. I believe K&R differs from ISO C in this definition, but I don't have the ISO C reference so readily available (in cached brain memory). Many computers - particularly small microcontrollers with simplistic memory hardware - can perfectly well store regular data at address 0; on those systems, programmers need to be extra paranoid about algorithm behavior. I can not find a reference that indicates such behavior is a strict violation of any standard C requirement. Nimur (talk) 13:50, 26 March 2013 (UTC)

Ok, my memory read through, and was correct: this behavior differs between C standardization efforts. NULL "may" be zero in K&R, and some of the K&R-esque GNU C; but ISO 9899 lays down the law for C11, and NULL shall be exactly the integer constan 0 as documented in ISO/IEC 9899:2011§6.3.2.3. So to answer the original question: "is it safe...?" Check which standard your C compiler is enforcing, or pass a standard on the compiler's command line. Alternately, enforce the condition with a preprocessor directive. Then it is safe to assume NULL explicitly equals zero. Nimur (talk) 14:02, 26 March 2013 (UTC)

I just had a look there and there doesn't sem to be any real change. According to the standard it is still okay for null pointers to be for instance -1 when stored in memory. For most systems one can assume that zeroing some store with memset will set any pointers in it to null but the standard does not say that. It just says that when one converts between a pointer and integer that 0 means a null pointer. Some old systems for instance had word addresses and the character pointer used the top two bits or a separate word. When converting to integer the two bits would be moved to the bottom and when converting back to pointer they would eb moved to the top. Even nowadays in C++ pointer to member functions for instance can do strange things. Dmcq (talk) 14:29, 26 March 2013 (UTC)

Even if one is assured that NULL==0, that's not sufficient to answer the original question. The OP's comparator safely holds iff pointer comparison is unsigned. Pointers themselves cannot be signed or unsigned (one cannot say unsigned void * p). I see nothing in C99 (6.3.2.3) about ordering of pointers, and all it says about comparison is to do with equality and inequality. One can cast pointers to integers (part 754) but the cast is implementation defined (part 755). It would seem overwhelmingly sensible for pointer comparison to be done unsigned, but that's not the same as that being mandatory (and there's always a weird architecture which does odd things for curious reasons). -- Finlay McWalterჷTalk 14:39, 26 March 2013 (UTC)

Two remarks. First, the C standard guarantees that the literal '0' in the source code, if used in a pointer context, will result in the NULL pointer. It does not e.g. guarantee that int i=0; int *p=(int*)i; will result in p's value being the NULL pointer, unless they changed either the standard or my memory. Secondly, there is, however, a guarantee that if you cast an pointer to an integer that is large enough, and then cast it back, you will get back the original pointer. Thus, there is a injective function from the range of intptr_t and the range of void*. You should be able use that to induce a total ordering on pointers. --Stephan Schulz (talk) 18:23, 26 March 2013 (UTC)

If the implementation provides uintptr_t or intptr_t (which is not required), it is guaranteed that casting a void pointer to one of those types and back yields a pointer that compares equal to the original pointer. You could ensure that the null pointer compares less than everything else by using uintptr_t and subtracting (uintptr_t) (void *) 0 from both sides. But I don't see any guarantee that p < q implies (uintptr_t) p < (uintptr_t) q or vice versa even when the pointer comparison is valid (i.e., when p and q point to the same array). -- BenRG (talk) 22:40, 26 March 2013 (UTC)

I violently agree. But if you need a total ordering on pointers where the null pointer is minimal, you can construct it. As you say, this total ordering does not necessarily extend the partial ordering on pointers defined in the standard. --Stephan Schulz (talk) 23:04, 26 March 2013 (UTC)

I don't have access to the published standard, but the last public draft (N1570) only says that NULL must be defined to be a null pointer constant, which in turn is defined as "an integer constant expression with the value 0, or such an expression cast to type void *". Even if NULL was required to be defined as the single token 0, it wouldn't follow that it would have to compare less than a non-null pointer, or that casting a null pointer to an integral type would necessarily yield the value 0, or that null pointers ever have an all-zero representation at run time. The only connection between the number 0 and null pointers is at compile time, when integer constant expressions with the value 0 are converted to null pointers where required by the type system. -- BenRG (talk) 22:40, 26 March 2013 (UTC)

Yes, you are right about the constant expression, not just literal 0. But the example I gave is not a constant expression, so it's still valid. --Stephan Schulz (talk) 23:04, 26 March 2013 (UTC)

Raymond Chen just posted a great example of a real world system where assuming a null pointer is zero (and therefore less than all pointers) would fail: [8]. In a Win32s program, NULL is represented by 4194304 internally. Pointers in the high end of address space would wrap around to zero and grow from there, and would therefore compare to less than NULL, assuming the comparision treated them as unsigned ints. 38.111.64.107 (talk) 14:57, 28 March 2013 (UTC)

I just came back to point out I was a bit off in how I first interpreted that. The pointer would still be represented by the numeric value zero, but when dereferenced would look up address 4194304. In this case, I suppose (assuming the compiler treats the pointers as unsigned ints) that the comparision would work. But the example is still good for pointing out that pointers are not just a direct index to a specific location in memory, which is why you can't count on null being zero. 38.111.64.107 (talk) 18:48, 28 March 2013 (UTC)

Samsung devices, Android versions, predictive text

I'm using a Galaxy S III Mini, with Android 4.1.2, with the default Samsung Keyboard, and the predictive text turned on. This works great. I also have the original Samsung Galaxy Tab, with Android 2.2. The predictive text is XT9, which I don't much like. Is there any way to get the current Samsung Keyboard as it works on my phone onto the Tab, or is it an issue of the later version of Android, and I won't be able to get the newer Keyboard and functions working on the older machine? Thanks if you can advise. — Preceding unsigned comment added by 193.173.50.210 (talk) 16:12, 26 March 2013 (UTC)

Sound emulation in E-UAE

The old fogies among you might remember I posted a question about sound emulation not working quite right in E-UAE on Fedora Linux some time in 2011 or 2012. Well, now that I have updated from Fedora 14 to Fedora 17, I tried it again. To my surprise, the sound in nearly every game worked right. The only exception so far was Ork, which had the same problems as before. But then I went to the "CPU" tab, and changed the "Speed" setting from "Maximum" to "Adjusted", setting the speed slider to as fast as it could go. To my surprise, the sound worked perfectly OK. When I set the setting back to "Maximum", the problem resumed. Having the "Speed" setting at anything other than "Maximum" slows the emulation of AmigaOS down terribly, so I prefer to keep it there in all cases except when I encounter sound problems. Does anyone have any idea what could be causing this? JIP | Talk 18:59, 26 March 2013 (UTC)

Furthermore, is it somehow possible to capture the sound output of E-UAE as a .wav or .ogg or whatever file? JIP | Talk 19:25, 26 March 2013 (UTC)

Personally I use the rec program that comes with SoX, but you can use any program that records audio, including Audacity, the Gnome Sound Recorder, or whatever. The trick of it is to configure your sound system to record the audio loopback. If your system uses PulseAudio (which some Google searching seems to be the default on Fedora), install the program pavucontrol. Set E-UAE running (so it's generating sound) and the recording program running (just to a disposable file). Then the recording program will appear in pavucontrol's "recording" tab. There you can configure the source that feeds it, and the record level. In my machine it's set for "monitor of built-in analog stereo" - you can tell it's working because the VU meter for that entry moves with the sound. The nice thing is that PulseAudio remembers the mapping in future, so subsequent runs of the recording program will automatically get the "monitor" settings without another reconfiguration (so you won't actually need to run pavucontrol again). Things should be much the same if, instead of PulseAudio, you use JACK Audio Connection Kit as the audio system: you'd use the program jack_connect instead of pavucontrol. -- Finlay McWalterჷTalk 09:49, 27 March 2013 (UTC)

This seems to have worked otherwise, but running both Audacity and E-UAE at the same time strains my system so much that while the sound doesn't miss beats any more, sub-second gaps of silence are inserted every couple of seconds into the sound. This of course shows up in the recorded file. So I guess I do need a faster computer after all. JIP | Talk 16:54, 27 March 2013 (UTC)

rec will be much less, because it has no GUI and only does negligible character animation as it's recording. On my system Audacity takes 41m of resident memory and rec 4m; Audacity uses 11% of (one core of) the CPU; rec uses about 1%. -- Finlay McWalterჷTalk 17:00, 27 March 2013 (UTC)

I tried rec, but the same thing happened, only to a marginally lesser degree. When running UAE without audio recording in the background, the sound is nearly flawless, but of course it is useless for recording purposes. So I think I need a faster CPU or more memory or something. JIP | Talk 18:15, 27 March 2013 (UTC)

ipad simulator poor sound quality

Hi all, I'm using Xcode with an ipad simulator, with a sound recorder, but the sound quality occasionally stuffs up. Basically it just comes out blurry, like I'm talking through a fan or something. This happens regardless of where I'm standing, but only occasionally. Does anyone know what's going on? I'm not registered with the ipad developer program yet (will be soon), so I can't test on the ipad itself. Is it a known problem, and does it apply only to the simulator? IBE (talk) 20:50, 26 March 2013 (UTC)

According to the Testing and Debugging in iOS Simulator page in Apple's iOS Developer Library, Microphone Input is not officially supported in the iOS Simulator, although it sounds like it is attempting to use the built-in microphone on the Mac. And it may be the actual cooling fan in the computer is causing distortion or noisy input. --Canley (talk) 02:19, 27 March 2013 (UTC)

Wow, thanks - useful link and very imaginative suggestion, although I find it slightly unlikely that it's the fan. Mic input would have to be compatible with the Mac itself, if not the simulator, so I doubt they would mess that up - still seems possible, however. IBE (talk) 07:54, 27 March 2013 (UTC)

UPS zip attachment fraud

I received one of the currently rife spam mails that says "The courier company was not able to deliver your parcel by your address. Cause: Error in shipping address." and has you double click on the attachment, which appears to be a ZIP file. Don't worry, I didn't do that! I'm just wondering how it is possible that a such attachments can still be so dangerous? For every little thing I'm asked three times to confirm that I really want to do it, and my computer updates itself at least every week, but security is apparently still so low that such an executable can still impersonate me and perform tasks that have no place in a ZIP file, and should clearly require admin permission. Editor030813 (talk) 22:00, 26 March 2013 (UTC)

Some people will click "OK" to let it run. You say you had to give approval three times for it to run, and some people will do that. That's why these things still work. RudolfRed (talk) 22:07, 26 March 2013 (UTC)

I don't know how often one has to click for this one; as I wrote, I didn't try it out myself. The number three, which referred to other situations, was a bit of a hyperbole; I assumed everyone knows these annoying confirmation messages, which sometimes are doubled, even in trivial cases. Editor030813 (talk) 02:15, 27 March 2013 (UTC)

The Snopes page says that the attachment is a zip file containing an executable file, so I assume opening the zip file is not a problem unless you then double-click the executable inside it. As for why all major operating systems assume that you want to grant any executable full read and write access to all of your personal files as well as the ability to connect to any host on the Internet, it's because all major operating systems are awful. -- BenRG (talk) 22:50, 26 March 2013 (UTC)

Thanks for your reply. So, is there a better OS out there? Editor030813 (talk) 02:15, 27 March 2013 (UTC)

Ben is probably referring to better security on Unix and Linux systems, due the permissions paradigm set up for all users (and programs). I believe it is generally agreed that such systems have the potential to be far more secure than Windows systems. If you want to start an argument fast, we can discuss whether OS X is more secure than Windows as-shipped :) SemanticMantis (talk) 12:50, 27 March 2013 (UTC)

I thought of that, but then thought that can't be what he meant, since Unix/Linux clearly is/are a major operating system. Anyway, the reason why I asked here was because I find it hard to believe that such a basic situation still hasn't been solved; it feels as absurd as if people were bemoaning that burglars keep coming in their house, while it has a big opening facing the street. But it seems the consensus here so far is that yes, the house has a big gap that nobody cared to close. My intention is not to trigger an argument about which is the best OS, but rather to understand why this hasn't been fixed yet. Editor030813 (talk) 19:08, 27 March 2013 (UTC)

It depends on what you mean by "major", but according to desktop usage share, *NIXes don't count. See Usage_share_of_operating_systems and this external page [9]. Non-windows, non-OSX OS's make up 0.05% to 2% of desktop usage share. So, unless we're talking about servers or super computing clusters, there are basically two modern (families of) OS's: Windows and OSX. There are hundreds of esoteric OS's out there, but almost nobody uses them. SemanticMantis (talk) 19:38, 27 March 2013 (UTC)

Well, what counts as "major" is indeed debatable; on the other end of the scale of possible arguments, one might count Android among the *nixes and discount OSX and iOS for only running on specialized hardware. (They're not an alternative unless you're willing to discard your existing hardware.) But be that as it may; I'd rather get back to my original question, which I may rephrase as:

Why is this still a problem? The answer "because Microsoft sucks" is not really satisfying. Even if that were the reason, there are plenty of inventive people around, they often have provided third party solutions for something MS failed to address. Editor030813 (talk) 20:13, 27 March 2013 (UTC)

I was talking about about the user-oriented model that's used in NT and Unices, where new processes normally get all the permissions of the process that created them, even though the process that created them is likely to be a standard shell and the new process is likely to be some random program you downloaded from the Internet. That makes sense when a machine has many users and you only care about protecting them from each other, not from themselves, but that hasn't been the right model on desktop or server machines for decades. Web browsers and smartphone OSes implement a more sensible security model as an extra layer on top of an OS with the standard near-useless model. We also have "hypervisors" that run multiple well-isolated VMs on the same physical hardware—which is what an OS is supposed to do—and provide useful features like process migration with hot backups and failover, which, again, the OS should do. We're stuck with this setup for the usual reason—backward compatibility—and also because once a design has been standard for long enough, people stop noticing its limitations. -- BenRG (talk) 21:02, 27 March 2013 (UTC)

March 27

email on Surface RT

Earlier this month my daughter got a Surface RT. She says that there is an email program but it doesn't work with our ISP. Is there a way to get it to use our ISP? Or is there an email program she can download that will work with our ISP? Or is there a different server that will work with the Surface RT email program? (She doesn't want to use web-based email.) Bubba73 ^{You talkin' to me?} 00:32, 27 March 2013 (UTC)

As to the first part of your question, seemingly "no". Most clients use Post Office Protocol (or sometimes IMAP) to access email on mail servers. For Surface RT, Microsoft says the mail app "doesn't support adding email accounts that use POP". Their only suggestion, bar webmail, is "look for an app" in their store that does do POP. -- Finlay McWalterჷTalk 00:44, 27 March 2013 (UTC)

Incidentally this eWeek story claims this particular deficiency is the cause of many Surface RT returns, and says that as of the start of this month "There are no third-party email apps that support POP". I can't actually find the darn App Store myself to search to see if that's true. -- Finlay McWalterჷTalk 00:50, 27 March 2013 (UTC)

The Windows Store. Bubba73 ^{You talkin' to me?} 01:22, 27 March 2013 (UTC)

Actually the story doesn't say it is the cause. It says it likely is. In other words, they appear to be randomly speculating on the cause, with no actual evidence (it doesn't sound like they even asked one store if they had any returns for the reason). There could be plenty of other reasons for the returns, e.g. people not being aware of the lack of a proper desktop (since you can't install such apps other then Office), people not being aware it can't support x86 apps, people who find the tablet crap etc. BTW, I couldn't find any POP supporting clients in the Windows Store. As mentioned by the story you can set up a number of providers like Gmail and Outlook.com to download POP email from other providers. So one option is to use such a provider which also provides IMAP support for access to your mail (like Gmail) or perhaps Exchange Activesync (like Outlook.com I think). Nil Einne (talk) 01:55, 27 March 2013 (UTC)

IMAP has been popular and preferred over POP for a long time now - has she double-checked with her ISP that there is no IMAP server she can connect to? 38.111.64.107 (talk) 12:33, 27 March 2013 (UTC)

Vimeo hosted video, access denial

Hi-- this self-proclaimed internet broadcaster uses Vimeo to host their videos. They claim half a million people watched the trailer to the current episode on Brampton.

<iframe src="http://player.vimeo.com/video/62519592?title=0&byline=0&portrait=0" width="760" height="427" frameborder="0" webkitAllowFullScreen mozallowfullscreen allowFullScreen></iframe>

Is there any way to see even their channel, let alone the video? -- Zanimum (talk) 13:23, 27 March 2013 (UTC)

No. This appears to be a feature of Vimeo's 'PRO Membership': "As a Vimeo PRO member, your account and your videos are automatically hidden from Vimeo.com since PRO allows for commercial use." - Cucumber Mike (talk) 22:08, 27 March 2013 (UTC)

"SUMMER STORM"

hello Sir, Actually I want to know about the "summer storm" which occurs due to the increasing temperature.How it effects the networking field? — Preceding unsigned comment added by Tanubapun (talk • contribs) 18:52, 27 March 2013 (UTC)

First let's consider the signal: High winds can blow down telephone lines where they are mounted on telephone poles. Lightning strikes from electrical storms can also damage them, and attached equipment, or even underground copper wires. Underground fiber optic technology is the safest way to connect your network to protect from storms. As for wireless technologies, lightning can also cause interference in those, and high winds can blow exterior antennae out of position.

Next let's consider electricity: Power is often interrupted and/or surges, due to storms. An uninterruptible power supply with surge protection should be used for critical systems, and at least a surge protector for non-critical systems.

For the most critical system, like the control room in a nuclear power plant, the facility should also be hardened against tornadoes, hurricanes, forest fires, and flooding, depending on location. Backup electrical generators may be needed for long-term power. StuRat (talk) 21:59, 27 March 2013 (UTC)

computer specifications

I'm trying to find out what would be the best sort of computer to get for the software I use, and apparently I want one that, amongst other things, has a good 'stack memory'? I have no idea what this is, though, or where to find out how different pieces of hardware compare. any help?

Kitutal (talk) 19:11, 27 March 2013 (UTC)

What kind of software is it, and where did you read about "stack memory"? I think there's no such thing. There are stacks, which are stored in memory, but there isn't a special kind of memory for stacks. -- BenRG (talk) 19:53, 27 March 2013 (UTC)

There are special registers and machine language operations that are specifically used for stack manipulations, so in principle there could be differences in their quality for different machines. But beyond that I cannot go. Looie496 (talk) 20:03, 27 March 2013 (UTC)

There is such as thing as "stack memory." Some microprocessors have it. However, I've never heard of it in x86 desktop processors (not saying it doesn't exist; I just don't know about it). (Addendum: I'm guessing whoever told you really meant for you to have a lot of RAM, but that's the best I can do without context.) --Wirbelwind(ヴィルヴェルヴィント) 21:51, 27 March 2013 (UTC)

I think they said I needed it alongside the RAM, I wasn't really paying attention. I guess it doesn't matter. Anyways, now I think I know what I want, just not where to get it. Anyone know where I might find an AMD FX-6350 CPU? none on their website or amazon, do they still sell them anywhere? Kitutal (talk) 22:07, 27 March 2013 (UTC)

'Still'? I'm not even sure they launched properly yet [10] [11] (although some sources claim they've been shipping in OEM computers since October). In any case it sounds like they're OEM only which may explain the difficulty finding them. Nil Einne (talk) 00:05, 28 March 2013 (UTC)

"Cache memory", maybe? -- BenRG (talk) 02:54, 28 March 2013 (UTC)

I thought that at first, but I don't think stacks are implemented in cache. --Wirbelwind(ヴィルヴェルヴィント) 04:13, 28 March 2013 (UTC)

I mean maybe the OP misheard "cache" as "stack", since this was apparently communicated orally. -- BenRG (talk) 05:25, 28 March 2013 (UTC)

Any software runing on a normal desktop processor won't need anything special for stack memory. A running program will use a part of it's allocated memory as a stack, but there isn't anything you need to worry about for that when selecting a computer. If your software gave you an error about being out of stack memory, you can probably assume that it was out of memory in general. That is usually a sign that you're asking the program to do more than it can handle, or it has run into a bug that causes it to eat through memory. Even if you only have a half gig of memory, your operating system will use a pagefile to let the program use much, much more, but at the expense of performance.

If you let us know what software in particular you are interested in running we can help you decide what is needed. Since this is a reference desk, I suppose I should point out the best reference is probably the system requirements list for the software you want to run. 38.111.64.107 (talk) 12:17, 28 March 2013 (UTC)

March 28

Vorbis codec for VLAN

An easy question, I hope; I just haven't found anything online (or rather, I've found too many things).

WP only takes ogg audio format, correct? I cannot convert in VLAN, because I lack the codec. Any idea where I can find one?

Thanks — kwami (talk) 07:23, 28 March 2013 (UTC)

http://ffmpeg.org hosts FFMPEG, including a codec library and a command-line tool that can re-encode. Nimur (talk) 09:24, 28 March 2013 (UTC)

Thanks, I'll check it out. Can one of them be imported into VLAN? — kwami (talk) 18:57, 28 March 2013 (UTC)

palindrome in a palindrome ?

Hi
does anyone know how to solve this pushdown automaton?
l={w contains a,b,c,n>1,w=R{w}|w^n}
Thank you.Exx8 (talk) 13:24, 28 March 2013 (UTC)

Youtube - I can see but cannot hear

I'm having a problem with hearing youtube videos. My speakers are fine, and I can hear videos generally, but ones I access on youtube - complete silence. This has been happening now for about 2 weeks. I've tried everything I can think of; fiddled with every sound setting I know; looked on Help for similar problems, but all I see is a bunch of people with the same problem I have and nobody's getting any solutions.

Can anyone suggest what I can do to hear youtube videos as well as see them?

Thanks. -- Jack of Oz ^[Talk] 13:38, 28 March 2013 (UTC)

Can we assume that you've tried everything at http://support.google.com/youtube/bin/answer.py?hl=en&answer=58132 ? If so, and if you have (or can download) VLC Media Player, you could try this. If the streams work through VLC, that pretty much narrows it down to an issue with Flash on your browser. - Cucumber Mike (talk) 13:57, 28 March 2013 (UTC)

Instruction 2 says "Adjust the volume control located in the lower left corner of the YouTube Video Player". I assume this refers to the screen I get when I access any utubular video. It has a microphone icon at the lower left of the screen. The only settings are Mute and Unmute. I cannot adjust the volume any other way. If I right click, I get a Settings tab, but it contains no options for volume control. So, how come I'm missing this adjustment capacity?

I have the most recent version of Adobe Flash. Would uninstalling and reinstalling it do any good? -- Jack of Oz ^[Talk] 21:45, 28 March 2013 (UTC)

(Blush) Stop the presses. Problem solved. I'm too embarrassed to admit what I was overlooking. Thanks for your help. -- Jack of Oz ^[Talk] 21:49, 28 March 2013 (UTC)

Ok, now I'm intrigued... - Cucumber Mike (talk) 21:52, 28 March 2013 (UTC)

OK, I'm not too proud. Allow me to bare my soul for your delectation. When I hover over the microphone icon, there's a red scroll bar. Immediately to its right is the digital clock counting away the seconds. Because of that proximity, I misread that scroll bar as the same thing as the red scroll bar above, the one that shows how far into the video you're at, at any point in time. I spectacularly failed to notice that the top scroll bar has a circle thing that moves along but the bottom one has a bar that never moves unless pushed by the user. In fact, it didn't register with me that they were even different things. In my so-called mind, there was just the one scroll bar, and it had nothing to do with volume control.

I comfort myself with the assertion that I cannot possibly be the first person to have made this mistake. Which means I fail Samuel Beckett's dictum: "To be an artist is to fail as no others dare fail". But I have failed magnificently, and that shall be my solace any my consolation. (You may now all cease your pathetic sniggering and get on with what you're paid for.) -- Jack of Oz ^[Talk] 22:22, 28 March 2013 (UTC)

What algorithm do browsers use to interpret HTML colors?

I understand that the standard system of Web colors is a hex number with each pair of digits corresponding to red, green, or blue, and that there's also a set of color names you can use, like "limegreen". But I've found that any string can be put into bgcolor="COLOR", and not all such strings are the same color. For example, "rainbow" is a shade of green and "chris" is red. The results seem consistent across browsers. How is the browser determining the corresponding color? ± Lenoxus (" *** ") 15:35, 28 March 2013 (UTC)

Hmm, I didn't know that. Experimenting, it seems to work only on the body tag and only with bgcolor html attribute, not with a CSS background-color specification and not on another tag like a div. Further, it's not just picking out valid hex chars, and not the first few letters - it does seem to be some kind of summing algorithm. -- Finlay McWalterჷTalk 16:03, 28 March 2013 (UTC)

Per below, it is picking only hex chars, but it's doing so in a way that confused my simple test. -- Finlay McWalterჷTalk 16:51, 28 March 2013 (UTC)

I did some digging through the Firefox source code, and the relevant code seems to be NS_LooseHexToRGB in gfx/src/nsColor.cpp, which says it implements the WHATWG recommendation rules for parsing a legacy color value. The significant part is that it trims first from the right (up to 8 chars for each of the 3 components) and then parses leftwards, pulling out upper and lower case hex chars. -- Finlay McWalterჷTalk 16:42, 28 March 2013 (UTC)

How does bitcoin work?

Hi,
Can anyone explain me simply how does bitcoin work?Exx8 (talk) —Preceding undated comment added 16:04, 28 March 2013 (UTC)

The best start is to read the intro to our article on the topic Bitcoin, and then to read the Bitcoin wiki FAQ ([12] although we don't link it in the article and the site seems to be down right now; google has a cache of it though) which is a good introduction. If you have questions after that, ask them. There are 3 or 4 distinct concepts going on so tackling each in turn is the best way to start. Shadowjams (talk) 16:11, 28 March 2013 (UTC)

A very short explanation for someone just trying to wrap one's head around the basics of it, as I understand it. To make sense of Bitcoin, first you need a slightly better-than-average understanding of what a currency is in the first place:

• All currencies can be considered representations of value. A dollar bill is just a piece of paper with writing on it, but because other people are willing to say it has value, I can use it as a currency and exchange it for something else of value (say, a piece of candy). The value of currency is not always stable — fifty years ago, I could have bought a lot more candy for a dollar than I could today. If everybody turned around tomorrow and said that the dollar has no value at all, then it would just be paper again.
• Most currencies are backed with something else. It used to be, for example, that a dollar's value was backed by a given amount of gold in a bank somewhere. (Currently, the US dollar is a fiat currency, backed only by the assertion that the US government says it has value.) Why gold? Because there is a limited amount of gold in the world, and it is difficult to get, and it is pretty stable as far as worldly objects go. For these reasons gold (and silver, and other precious metals) have long been the basis of currency regimes. If it turned out, tomorrow, that there was an unlimited amount of gold in the world, and it was easy for anyone to get it, gold would lose value very quickly, and be a bad choice for currency.
• OK, if you're with me so far... the idea behind Bitcoin is to use information as a means of backing a currency. The Bitcoins themselves are based on mathematical problems that are hard to solve. So the effort it takes your computer to solve these problems is equivalent to the effort it would take to mine gold. So the answers to the problems are more or less the backing of the currency. There are other aspects to it (e.g. it uses peer-to-peer networking as a means of exchanging and verifying the value of the information, instead of a central bank, and making sure that information isn't counted twice), but that's kind of the basics.
• So why should anyway value the answers to these mathematical problems? The same question can be asked for why you would value gold, or value pieces of paper with the word "dollar" written on them. They have value so long as people are willing to say they have value. If you have three Bitcoins, and someone is willing to give you something else for them, suddenly they are equivalent to any other form of "money" you can imagine.

So will Bitcoins retain value? Is investing in them a good idea? Can they really be used as an alternative to national currencies? Nobody really knows at this point; there are lots of opinions pro and con as to what the long-term prospects are. At the moment they seem to have value to some people, but that doesn't mean they will tomorrow. There are lots of questions by real economists about whether this can really work out. --Mr.98 (talk) 16:44, 28 March 2013 (UTC)

That's a good overview of the currency aspects. The technical aspects involve solving these core problems:

1. How do you stop people from spending the same money twice
2. How do you stop someone from spending someone else's money
3. How do you create money in the first place (in a way that inspires confidence)

One and two are easy (or easier) with physical currencies. When you give it away it's gone, and when you have it nobody else can give it away. The third is the reason we have banks, and more specifically central banks. Bitcoin addresses the first problem with what it calls a "block chain" which is essentially a giant transaction log of every bitcoin ever spent, and who currently owns it. The second is addressed through public key signatures, when you send money you do so by signing a transaction that says I give x bitcoins to y. Everyone else uses the block chain to make sure you own the bitcoins you're giving to y, and then checks the signatures to make sure only you signed the transaction. The third is done through "mining." Put simply, as the block chain gets created, people randomly are given coins (not actually randomly, it's more of a lottery and your odds are proportional to how much computing time you dedicate to mining).

Any one of these points, and some others along the way, have more technical pieces to them. Shadowjams (talk) 17:37, 28 March 2013 (UTC)

Windows 7 problems

I recently upgraded from Windows XP to Windows 7, and I found a few things that give me problems with it.

1) I use mIRC 6.2, which was released before even Windows Vista came out, because I like prefer it over more recent versions. As far as I know, user data from applications programmed to "recognize" it will put their data in C:\Users\<user>\AppData , but since 6.2 is pre-Vista, it still stores its data in C:\Program Files (x86)\mIRC (in my case, x86). Now, mIRC stores its logs within its subfolder, and when I recently went to find that folder, it was not there. Unhiding hidden + system folders did not help. However, I remembered that WinRAR could see hidden folders on my XP machine by default, so I browsed there with it, and voila, there it was. Why is Win7 completely hiding the logs folder from my view? Is it because it's not in the AppData folder?

2) Windows 7 changes (Windows/File) Explorer and file select/save dialogs in many ways that I do not like over XP. I use Tab all the time to navigate over various selections. For example, in XP, if you pressed Shift-Tab in the area where you would type in the file dialogs, it would go directly up to the file list (where I would then use the arrow keys or type in the beginning of the file name). In 7, it goes up to the "Date modified" column. Is there any way to change this back so that it goes directly to the file list?

3) Windows 7's search (bar) is useful in some places, but not in others. Is there a way to restore or emulate the way XP used to do its search? In addition, is there a way to remove the "Search programs and files" textarea from the Start Menu? (I used to browse the Start Menu with my keyboard, which is now impossible without hitting Shift-Tab first, small, I know)

4) Is there a way to restore the Favorites menu-bar item in 7? That's the way I used to use to primarily get around my system (again, keyboard and typing; in this case I would type Alt+A [brought up Favorites], then type the letter of the shortcut in my Favorites that I wanted to go to).

5) In XP, using Backspace would go up a directory. In 7, you need to do Alt+Up. Is there a way to change this back?

Thanks! -- 143.85.199.242 (talk) 16:33, 28 March 2013 (UTC)

1) I suspect the logs are really in the VirtualStore directory, and you will see them in Explorer if you look there. 2-5) Classic Shell can fix a lot of Vista/7 UI regressions, but I don't know whether it can fix the ones you mention. You can also use a program like AutoHotkey to set up convenient keystrokes to replace the missing built-in ones. -- BenRG (talk) 22:43, 28 March 2013 (UTC)

Medieval Toal War (original)

How can I get another cd/dvd of this game??? I played mine so much I wore it out! It won't even load anymore... — Preceding unsigned comment added by 24.117.101.191 (talk) 18:34, 28 March 2013 (UTC)

Software (preferably free or inexpensive) to remove someone from a personal video on my hard drive?

Sorry if this sounds stupid but I once heard a director say that he would "digitize that out" in regards to something he wanted to get rid of in a movie. I have a few personal videos on my hard drive that I'd like to completely remove one annoying person from. I don't see how this could be done but if a Hollywood director mentioned it I figure it must be a real editing technique. What software, free or inexpensive, will do that? Cowgirl174.65.24.110 (talk) 01:47, 29 March 2013 (UTC)