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September 7

running out of letters

Lately Firefox (before and after the latest version) does a weird thing: on some websites, ‘y’ and ’z’ do not show up at all and ‘x’ appears as ‘"’. Is it just me?

Sites where I've seen this, so far:

www.matrix.nwmls.com
www.doesnotplaywellwithothers.com
boardgamegeek.com
dieselsweeties.com
www.channel101.com
www.esperanto.mv.ru (affecting ‘z’; ‘xy’ do not occur in Esperanto)

—Tamfang (talk) 04:37, 7 September 2019 (UTC)[reply]

Sounds like some part of the memory where the fonts are stored was accidentally overwritten by something else. This could be caused by running a program that has a bug in it. If so, a reboot would likely fix it until that program is run again. If that doesn't fix it, maybe Firefox itself has been corrupted, in which case you would need to uninstall it and download again. SinisterLefty (talk) 10:32, 7 September 2019 (UTC)[reply]

Well, more than one font is affected. —Tamfang (talk) 20:01, 7 September 2019 (UTC)[reply]

One program can not access the memory allocated to another program. Each program has its own isolated memory space. Ruslik_Zero 20:05, 7 September 2019 (UTC)[reply]

@Ruslik0: Cheat Engine. Poveglia (talk) 00:13, 8 September 2019 (UTC)[reply]

@Ruslik0: Not technically correct, see shm_overview(7). If you're still on Windows there is bound to be an equivalent. Martin of Sheffield (talk) 09:20, 8 September 2019 (UTC)[reply]

There are several different methods to access the memory of another process in Windows. Cheat Engine uses the KeStackAttachProcess function to access the memory, but it is also possible to do direct memory mapping using the CR3 of the process, or hijack a thread of the target process to open the destination process and copy it to there, etc. Poveglia (talk) 10:43, 8 September 2019 (UTC)[reply]

These are malicious programs. Normal software can not cause such a defect. Ruslik_Zero 13:30, 8 September 2019 (UTC)[reply]

That is simply not true; a debugger is normal non-malicious software and it can access and manipulate the memory of another program. Its also not a defect but the way its intended to work. Something like KeStackAttachProcess is a documented feature, not a defect/bug. And calling a program that allows someone to cheat in a singleplayer videogame "malicious" is rather weird; CE only does stuff the user wants it to do while malicious software does stuff the user does not want it to do. Poveglia (talk) 13:33, 8 September 2019 (UTC)[reply]

You are implying that this user wanted to drop some letters from Firefox? Ruslik_Zero 20:34, 8 September 2019 (UTC)[reply]

@Ruslik0: No, I am not. Please re-read the above. Poveglia (talk) 00:33, 9 September 2019 (UTC)[reply]

@Ruslik0: I think I get it. Your use of the word defect was probably referring to OP's post, not to your comment from 20:05. I've tried to explain that that comment is incorrect, but I haven't attempted to answer OP's question. Poveglia (talk) 08:41, 9 September 2019 (UTC)[reply]

I am surprised that we are so sure this is a memory-corruption bug. Tamfang has given us very little information to go on - we don't know the OS, hardware, any configuration. Off the top of my head, this could be a network bug - is he using a proxy, a cache server, or anything that may be interposed? Are there plugins or extensions able to manipulate webpage data? Does the bug occur when he prints, views source, copies to clipboard, or saves the page? There are innumerable of OS- and DE- and hardware-dependent variables at play as well. Screenshots and more details would be helpful. Elizium23 (talk) 05:32, 11 September 2019 (UTC)[reply]

Indeed. The best we can say is that an unusual bug has occurred; it would be good to report it by following the official Firefox bug report guidelines. There are innumerable possible causes and it's very premature to diagnose this based on what Tamfang has provided. A cursory web-search shows that this issue is not "very common" and there is no "simple" fix for an end-user. We should direct him to file a report to the Firefox experts. We can all speculate wildly based on our previous experiences; but the truth is, we don't even know what broke, or even if Firefox application-software is the only item affected. Software debugging is too complicated to meaningfully speculate about a specific root-cause. I am frankly baffled why the early responses to Tamfang's question provided such apparent certainty about one specific and largely ill-formed hypothesis.

Nimur (talk)

You both seem to have missed the last line in my initial post: "If that doesn't fix it, maybe Firefox itself has been corrupted, in which case you would need to uninstall it and download again." I didn't speculate on how that corruption might have occurred. SinisterLefty (talk) 20:16, 11 September 2019 (UTC)[reply]

Thanks for all your remarks. I'm on a Macintosh. It's not a network issue: I've seen the effect on a local file (though, strangely, not other local files that use the same CSS). It's probably not a corruption of my fonts: multiple fonts are affected in exactly the same way, and it doesn't happen to the same pages in Safari. I removed Firefox and downloaded it anew, with no visible change. —Tamfang (talk) 22:28, 11 September 2019 (UTC)[reply]

Let's all chip in and buy @Tamfang: a new computer, that is probably easier than diagnosing this mysterious problem. Poveglia (talk) 06:33, 12 September 2019 (UTC)[reply]

Great, I'm about ready to try Linux again. —Tamfang (talk) 07:20, 12 September 2019 (UTC)[reply]

September 8

GeoFs and intel core i7

Why is this game so laggy with an core i7 and it is very fast with an core i5 --Thegooduser Life Begins With a Smile :) 🍁 22:10, 8 September 2019 (UTC)[reply]

Which i7 and which i5? Did all other components of the computer stay the same? I am pretty sure that human life begins with a crying baby, and if the baby does not cry it will get some help. Poveglia (talk) 00:54, 9 September 2019 (UTC)[reply]

The oldest i7 vs the latest i5 is not a fair battle https://cpu.userbenchmark.com/Compare/Intel-Core-i7-920-vs-Intel-Core-i5-9600KF/1981vsm772658 Poveglia (talk) 00:59, 9 September 2019 (UTC)[reply]

I am talking about core i7 8th gen and a i5 from 2013--Thegooduser Life Begins With a Smile :) 🍁 01:08, 9 September 2019 (UTC)[reply]

How much RAM does each have ? SinisterLefty (talk) 01:45, 9 September 2019 (UTC)[reply]

SinisterLefty 12GB --Thegooduser Life Begins With a Smile :) 🍁 01:57, 9 September 2019 (UTC)[reply]

Same graphics cards ? Same Ethernet speeds ? Same hard drive speeds ? Same O/S on each ? Both 64 bit versions ? If Windows, I suggest running the "Windows Experience Index" calculator, which may give clues as to the weak spot. SinisterLefty (talk) 02:23, 9 September 2019 (UTC)[reply]

What do benchmarks show? Bubba73 ^{You talkin' to me?} 03:07, 9 September 2019 (UTC)[reply]

September 9

Google Chrome won't let me click on tabs

I can click on other things, and I can CTRL TAB to page thru the tabs. Is this a bug or some setting that somehow got screwed up ? SinisterLefty (talk) 02:30, 9 September 2019 (UTC)[reply]

If you close Chrome, and then restart it, does it still have the same problem? Poveglia (talk) 02:52, 9 September 2019 (UTC)[reply]

The problem is intermittent. The next time it occurs, I will try that. SinisterLefty (talk) 03:28, 9 September 2019 (UTC)[reply]

September 11

Creating digital pictures and wallpaper

How are 3d wallpapers created? I am not a good painter with brush. Is it possible to create digital arts with any software using own imagination? — Preceding unsigned comment added by 2405:205:602A:13F4:B5BB:2306:846F:85B8 (talk) 07:12, 11 September 2019 (UTC)[reply]

If you're not good at drawing, you probably don't want to use a program like MS Paint. You could also use a pixel editor to make some repeating small geometric pattern, like cubes, by setting the color of each pixel one at a time. For computer generated 3D images, there are programs that allow you to specify the location and attributes of larger basic geometric shapes, like cubes, spheres, cylinders, etc. See 3D modeling, ray tracing and texture mapping. You could also apply textures, colors, lighting, etc., to complex 3D objects they provide. But to actually create your own complex 3D image, like a person, would require a great deal of time and expertise, to make it look any good. Also, some programs, like ray tracing, require significant CPU time, so you may have to wait for it to finish processing. Anther option is to do a screen grab of some 3D image you like, such as the victory screen on a game you won. Or you could start from digital photographs (perhaps from your cell phone) and then modify the image(s). For example, you could create an image of somebody about to be squished by a giant falling domino, by combining images of the person and falling domino, at different scales.

Note that making 2D images look like they are 3D can be done with techniques such as perspective and 3D projections. If you have some particular type of 3D image in mind, we might be able to suggest the best way to make it. Also, do you already know how to set an image as wallpaper ? SinisterLefty (talk) 12:32, 11 September 2019 (UTC)[reply]

Setting maximum JSON length property on JsonSerializer

I've run into a problem at work. I am using ASP.NET Core to build a controller taking JSON requests. The controller method looks something like this:

[HttpPost]
public IActionResult DoStuff([FromBody] MyModelClass model)
{
  /* Do something with the model */
  return new JsonResult() { /* parameters */ };
}

which is then supposed to receive HTTP requests with the Content-Type header set to application/json. This works all well and good, but then I found out that some of the request bodies are several megabytes long, which causes an error that the body length exceeds the maximum JSON length. And I couldn't find any easy solution to set a new value for the maximum JSON length. I tried googling for it, and found plenty of pages advising me to set the MaximumJsonLength property. But that only works for JavaScriptSerializer, and the ASP.NET Core framework seems to use JsonSerializer instead, which doesn't appear to have this property.

In the end I found this page advising me to write a custom input formatter, and this appeared to work. I just replaced all of this weird "protobuf" stuff with a JavaScriptSerializer that I was able to set the maximum JSON length property to. But it appears that this has caused the loss of all the pre-made JsonSerializer functionality.

What my question here is, is there any easier way to do this? JIP | Talk 20:44, 11 September 2019 (UTC)[reply]

The opposite approach is to modify your code to return the data in smaller pieces, or only return those portions which have actually been changed. This isn't always possible, but when it is, it could solve your problem. If you can describe what the code does, maybe we can think of ways to break up this task. SinisterLefty (talk) 21:08, 11 September 2019 (UTC)[reply]

No, the problem is not with returning data, it's with receiving data. It's the incoming requests that are several megabytes long, not the outgoing responses. JIP | Talk 04:06, 12 September 2019 (UTC)[reply]

September 12

I accidentally deleted 10 files on my USB memory/storage chip by overriding their names. Are they lost for good, or are they retrieveable?

I accidentally deleted some files on a Lexar USB memory/storage chip by changing the filenames of some other files to the name of already existing ones and then I overid them. It was a stupid and clumsy mistake.

Since they were overriden with the same name by other files they did not go to into the trash (recycle bin). in fact, I think they probably wouldn't have either way, since they were only stored on the USB chip and not on the PC itself.

Is there any way I can retrieve the files? There were only 10 files, I believe, so if they still exist and can be found, it shouldn't be a problem to restore them one at the time, I think. I'm no ace on computers, but if it can be done with relative ease, then maybe I can do it, with some guidance.

Thank You Krikkert7 (talk) 19:03, 12 September 2019 (UTC)[reply]

It will very much depend upon your operating system and the filesystem in use. For hard disks the advice is to connect them unmounted and use a block-by-block copy utility to make an image of the disk before trying any recovery. I suspect that this advice is valid for memory sticks, but do not have a firm statement confirming that - in other words, proceed at your own risk. The standard tool on Linux and UNIX systems is dd(1). At a presentation on security that I attended recently we were told: "Create the image with dd. Windows is not forensically safe.", you are effectively doing forensics here. Once you've made a copy, remove the stick and don't connect it again. Work on a copy of the online copy, if you screw up you just make another copy! Try sleuthkit as a starting point. The bad news is that recovering deleted files is rarely "done with relative ease". Martin of Sheffield (talk) 19:30, 12 September 2019 (UTC)[reply]

@Martin of Sheffield: Would ddrescue be better than dd (on a *nix system)? Poveglia (talk) 20:23, 12 September 2019 (UTC)[reply]

Good point, the new kid on the block! I've personally not used it, but the write-ups seem positive, particularly for hard disks which may be failing. In this case though the copy should be clean since we are not dealing with failing disks and head crashes. Martin of Sheffield (talk) 21:09, 12 September 2019 (UTC)[reply]

I can vouch for the fact that ddrescue works but I haven't had a reason to try dd yet (and I thank all deities for that). Poveglia (talk) 21:40, 12 September 2019 (UTC)[reply]

@Krikkert7: In the past there was a suite of Norton utilities that would show you deleted files and let you recover all or parts of them. You could check to see if that product or something similar still exists. I agree with the above advice to work on a copy if possible. RudolfRed (talk) 20:00, 12 September 2019 (UTC)[reply]

Like Martin said, first its important to make a proper copy. We have a long list of data recovery software. I'd imagine Recuva has a large marketshare amongst windows users because it was created by the same company who make CCleaner. Only run the data recovery software on the copy, not on the original! Poveglia (talk) 20:20, 12 September 2019 (UTC)[reply]

Yeah it's probably not a big deal to use a file recovery tool to get the files back, especially if you can tolerate some file corruption (e.g. the file was a document you were working on, and a paragraph got clobbered but the rest is intact). Maybe someone can suggest specific ones. I used to know of a few but their names aren't coming to mind right now. 173.228.123.207 (talk) 20:21, 12 September 2019 (UTC)[reply]

If this is Windows, I would also suggest Recuva. Provided that you don't modify anything on the USB drive, I wouldn't even bother copying this first. Just run Recuva and let it do its thing, but recover the files to an area on your normal disk, not the USB drive.

If you knew how to make an appropriate bitwise copy which was itself recoverable, you wouldn't be asking me for advice. Andy Dingley (talk) 20:39, 12 September 2019 (UTC)[reply]

@Andy Dingley: Are there no easy to use Windows programs that can do that? I wouldn't be surprised if something like the HDD Raw Copy Tool would work. Another less-desirable option would be AOMEI Backupper Standard or even EaseUS Todo Backup. Poveglia (talk) 21:30, 12 September 2019 (UTC)[reply]

Recuva's about as easy as it gets. Andy Dingley (talk) 00:08, 13 September 2019 (UTC)[reply]

I know, I mentioned it above and I've used it in the past. I meant easy-to-use Windows programs that can make a "raw" copy of 1 usb stick and write it to another. Poveglia (talk) 00:35, 13 September 2019 (UTC)[reply]

Thank you, guys. That was a lot more response than I expected. I'll try Recuva. It sounds like it might be the easiest thing to use. I have used/edited a few files since the accident, however. Not that many, but the point is that the USB has not been left untouched since the accident, if that matters... Krikkert7 (talk) 10:05, 13 September 2019 (UTC)[reply]

September 13