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Wikipedia:Reference desk/Archives/Computing/2013 December 17

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December 17

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How to delete Null Zeros in XML file?

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How to delete Null Zeros in XML file?

For Ex:

Input = Premium 00506.0800

Output = Premium 506.08

I want like the Output above. Please connect my name when anyone answer.--Tenkasi Subramanian (talk) 13:26, 17 December 2013 (UTC)[reply]

@Tenkasi: It's impossible to answer the question unless you tell us what software environment you're working in. XML is only structure, it doesn't determine process. Looie496 (talk) 17:54, 17 December 2013 (UTC)[reply]

Environment Means?

OS is Windows 7 and XML is stored from web (Internet Explorer) as Simplified XML format. Is it enough or some other details you want?--Tenkasi Subramanian (talk) 19:19, 17 December 2013 (UTC)[reply]

Well, maybe you will understand the problem better if I say that the simplest way to do it is to edit the file using a text editor (XML is just structured text), and erase those zeros. If you need to do it on too large of a scale for that to work, then you will need to write a program. But then it is necessary to know what sort of programs you are capable of writing. Looie496 (talk) 20:05, 17 December 2013 (UTC)[reply]
You could load the XML file into your text editor, and then run a global search and replace from " 0" (that's a space followed by zero) to just " " (space). When that completes, run it again and again until you get no replacements occurring. Save the result using a different file name - do NOT overwrite your original file in case this method removes a zero you didn't want to lose. For example, it will turn "Premium 0" to "Premium ".
You will get a better result if you can use a programmers' editor which can search on regular expressions. If you don't understand what regular expressions are, ignore this paragraph. If you have such an editor, ask just below this paragraph and someone more versed in such expressions than I will give you suitable search and replace terms.-gadfium 00:17, 18 December 2013 (UTC)[reply]
Can Word be persuaded to open XML files? If so, then the wildcards function in the replace tool is powerful enough for this. find " 0{1,}([1-9]{1,})" replace " \1" (without quotes, note the leading space on both expressions) finds a space, followed by at least one 0 followed by a string containing only the numbers 1-9, or a newline, and replaces it with the string (i.e. gets rid of leading 0s). For trailing 0s: find "(.[0-9]{1,}[1-9]{1,})0{1,}([ ^13^11,])" replace "\1\2" (without quotes, no leading space) finds any string starting with a . followed by at least two significant digits, followed by at least one 0, followed by a space, a comma or a newline, and replaces it with the decimal point and the significant digits followed by the space, comma or newline. find "(.[1-9]{1,})0{1,}([ ^13^11])" replace "\1\2" works for only one significant digit (but not if there is a significant 0 after the decimal point, e.g. 0.01000). More punctuation can be added into the final square brackets if needed (e.g. if you have something like: "process 003.04300;", then throw a semicolon in there. If you can't open the XML file directly, then copying the text into word and pasting it back into the file you want (making sure to keep the old file as a backup in case it all goes wrong) should work. MChesterMC (talk) 10:21, 18 December 2013 (UTC)[reply]
Forgot to ping Tenkasi MChesterMC (talk) 11:51, 18 December 2013 (UTC)[reply]
Notepad will work for most cases. My recommendation is to make copies of the xml file step by step and then to "save" changes rather than "save as" to avoid character coding issues. Alternatively, Notepad++ http://notepad-plus-plus.org/ is quite useful for editing xml files, if ordinary notepad wont work for you for some reason. DanielDemaret (talk) 11:53, 20 December 2013 (UTC)[reply]

Facebook

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Any way to prevent friends from seeing only the recent friends I added? thanks. Ben-Natan (talk) 17:11, 17 December 2013 (UTC)[reply]

You previously could, as of now no. 190.60.93.218 (talk) 19:10, 17 December 2013 (UTC)[reply]

Does anyone still use HTTP 1.0 anymore?

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There is a security flaw in older versions of IIS that deals with HTTP 1.0. To fix the issue, one of the options we are considering is to turn off support for HTTP 1.0. My question is, does anyone still use HTTP 1.0 anymore and if so, how many? HTTP 1.1 was finalized in 1997, so I would expect that nobody is still using HTTP 1.0, but how would I know such a thing? This Microsoft Knowledge Base article indicates that this maybe a problem with some Windows XP users. AnonComputerGuy (talk) 17:25, 17 December 2013 (UTC)[reply]

I've seen some proxies and some programs use only HTTP/1.0, so, I'm sure some would use HTTP/1.0, I don't think most notice, you don't support HTTP/1.0, But eventually someone will. 190.60.93.218 (talk) 19:12, 17 December 2013 (UTC)[reply]
Well, I'm going to see if I can gain access to our IIS logs to see if there are any 1.0 requests. (As a mere developer, I don't have direct access to our production servers. I have to go through a different team to see the log files.) AnonComputerGuy (talk) 19:24, 17 December 2013 (UTC)[reply]
I think there are still enough HTTP/1.0-only clients out there that disabling it would be problematic (see this thread for example). If you do look at the logs I'd be curious to know what you find (assuming you're allowed to tell). -- BenRG (talk) 08:07, 18 December 2013 (UTC)[reply]
I was able to examine our production server logs and the results were very surprising. 70% of our traffic is using HTTP 1.0. I was not expecting that. So, completely blocking all HTTP 1.0 requests is not a viable option. AnonComputerGuy (talk) 18:20, 18 December 2013 (UTC)[reply]

Memory Screenshow/Image states.

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I wouldn't know how to call this, actually, but in the past, I've used some Virtual Machines, using VMWare, I've noticed it has a pause button, and a screenshot button, (which saves the actual state/image of the computer, not a raster image). So basically it can stop any arbitrary program and run it again from where it was, also some emulators like NES, SNES, WII, PS1 seem to have some "save mode" which saves the whole state as it was.

I wonder if I could do anything similar with an executable, pause it, save it, and maybe restore previous states, is there anyway I can do this? (I'm using windows 7.)190.60.93.218 (talk) 19:08, 17 December 2013 (UTC)[reply]

Normally you would do that by running the program in a debugger. In order to re-start a program from an arbitrary state you need to create a core dump, which is generally more trouble than it is worth. Looie496 (talk) 21:32, 17 December 2013 (UTC)[reply]
And if the program has open files or handles (which it will) then there is pretty much no way to recover it perfectly after completely unloading it. The program doesn't run in isolation - it talks to the OS for all sorts of things, so the OS would need to be in the same state as well. Pause/unpause can be done with a debugger but usable save states won't happen. It works in virtual machines because the entire state of the system, including the OS, is saved. Katie R (talk) 13:16, 18 December 2013 (UTC)[reply]

Steve Wilson on YouTube

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Where is his video where he says "awful suffering" "the world will be in chaos" "it will not be business as usual"? it's almost certainly a may 21 (/may 21 2011) video.--78.156.109.166 (talk) 20:50, 17 December 2013 (UTC)[reply]

Recovering a replaced file

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My laptop is running Windows 7. I accidentally moved one file named "Note 1.txt" to another folder that contained a file of the same name. I accidentally clicked "Move and replace". How do I recover the file that was replaced? Is it deleted and then replaced? — Melab±1 23:40, 17 December 2013 (UTC)[reply]

The contents of the file will very likely still be present, unless you've done other things with that disk in the meantime, but you'll probably need file recovery software to get it back. Meanwhile: don't use that disk. Looie496 (talk) 23:55, 17 December 2013 (UTC)[reply]
How can I recover the file then if I can't use that disk? What software should I use? It doesn't make sense. — Melab±1 01:13, 18 December 2013 (UTC)[reply]
I believe that he means that you shouldn't use the disk until you begin recovering the files. This is because NTFS "deletes" files by allowing them to be overwritten. The actual information is still there, if one looks closely. But, by using the disk, you run the risk of writing over that information.
I used ntfsundelete on a folder containing several gigabytes of information, once. Σσς(Sigma) 07:20, 18 December 2013 (UTC)[reply]
(ec) Recuva is a good undeletion tool for Windows. The data from your file will remain on the disk until it's overwritten with something new (unless it's an SSD, in which case the data is probably gone already). If you install Recuva on that disk, the files making up Recuva might overwrite the file you're trying to recover. Most other "uses" of that disk will create new files as well (for example, web browsers write files to their disk caches). Your safest bet is to download Recuva on another computer, install it to a USB stick or other external storage, plug that into the afflicted computer and run Recuva straight off the USB stick. You should also save the recovered file to the USB stick. Once it's successfully recovered, you can move it to where it belongs. -- BenRG (talk) 07:25, 18 December 2013 (UTC)[reply]
I used Recuva but the files its showing me seem to be ones that HAVEN'T been deleted. — Melab±1 19:03, 18 December 2013 (UTC)[reply]
Isn't there a possibility that the data has already been overwritten when the contents of the file were replaced with the new contents. If the new file was longer then it may well have been written to a new location, retaining the old contents, but if the new file was shorter, a portion of the old file may have been irrevocably overwritten. Does anyone know the approximate probability of overwriting on a modern hard drive? Old floppy drives tended to use the first available space, but modern file systems and controllers are much more sophisticated. I know that overwriting is unlikely on flash memory where new contents are normally written to new space, even with a file of the same name, but won't most operating systems and hard drive controllers use the same space over again for a shorter file of the same name? Dbfirs 08:06, 18 December 2013 (UTC)[reply]
To partially answer my own question ... I was thinking of the old FAT system where the old contents would almost definitely have been overwritten if the new file was shorter. I think under the NTFS transactional system there is a high probability that the new file was written to new space and then the old file subsequently deleted. Have we an article that explains the process? Dbfirs 08:18, 18 December 2013 (UTC)[reply]
"Move and replace" doesn't overwrite the replaced file, it just deletes it and then proceeds with the move as though it had never existed. If you moved the file from another folder on the same disk then it almost certainly just updated directory entries and didn't touch any file data at all. On NTFS that means it just marked the replaced file's MFT entry as deleted/available, changed the parent directory in the moved file's MFT entry, and updated the directory indexes. Directory indexes are stored as files and can overwrite file data when they grow, but in this case neither directory grew in size, so I think that won't happen. Recuva and similar utilities just read the MFT and ignore the indexes, so you can always recover the file immediately after the move in this scenario. On FAT, the directory "indices" are the only record of a deleted file's former existence, and I think there's a good chance that the moved file would overwrite the deleted file's entry, making the file data much harder to recover (though it would still be there).
If the move did copy file data, I think there's a very good chance that it picked a different location on the disk to put the copy, especially if you have a lot of free space. I think you're right that the chance is higher on a transactional filesystem, but I don't really know. -- BenRG (talk) 08:46, 18 December 2013 (UTC)[reply]
Thanks for the clarification, and apologies if I seemed to be doubting your original reply. (My brain tends to get stuck in its memory of outdated systems.) I agree that there is a high probability that the original file contents are still there, and that the probability gradually reduces as the disc is used. My old version of Windows (Vista) seems to spend a lot of time on boot-up writing many small files, some of them for reasons that are not clear to me (though I expect it has good reasons for writing them). Presumably any of these could overwrite the sectors where the original file was stored, so booting from a USB or CD will be important. Dbfirs 09:11, 18 December 2013 (UTC)[reply]

Recovering a lost file is elementary. Place the mouse cursor on the file name in Windows Explorer, right click and go down the options. You will see "Restore Previous Versions." click on that and it will give you the choice of dates. You should choose the date which predates your unfortunate move and your file will be restored. You can also do it with the whole sub directories as well. AboutFace 22 (talk) 15:15, 18 December 2013 (UTC)AboutFace_22[reply]

Well, yes, we've all being assuming that Melab-1 has no backup of the lost file. Obviously, the first thing to try is restoring the file from a backup. "Restore Previous Versions" will work only if Windows Backup has been run since the lost version was created (or if a backup was created with a restore point). We've been giving advice on the assumption that there is no backup available. The Recycle Bin will not have a copy of the deleted file if it was deleted as part of a move. Dbfirs 11:01, 19 December 2013 (UTC)[reply]

You are right about that. The backup and restore option must have been set up for that to be effective. I am not sure but is it not a part of a default windows configuration, a part of "Windows for dummies?" AboutFace 22 (talk) 16:28, 19 December 2013 (UTC)AboutFace_22[reply]

I haven't seen it set up as a default, but some suppliers might do so. We all just assumed that Melab-1 was intelligent enough to have looked for a backup before asking the question. Dbfirs 18:48, 19 December 2013 (UTC)[reply]