Wikipedia:Reference desk/Archives/Computing/2021 May 3

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May 3

File directory question

Is the diagram at Directory (computing) in the Overview section correct? File2 is in two directories. What happens if you delete it from one of the directories? Bubba73 ^{You talkin' to me?} 03:28, 3 May 2021 (UTC)

If you delete it from one directory, it can still be accessed from the other one. If you delete it from all directories, then it can't be accessed by normal means, and the disk space is available for reuse. See hard link for more details. All filesystems on Unix systems support multiple hard links, as far as I know. NTFS also supports them.-gadfium 03:47, 3 May 2021 (UTC)

OK. Many times I have a copy of a file in more than one directory (in Windows), but they are actual physical copies. Bubba73 ^{You talkin' to me?} 04:13, 3 May 2021 (UTC)

Similarly, hard links also allow the same file to have two or more different names within a single directory, if you want that. If you delete one name, the other one (or more) will still exist. --184.147.181.129 (talk) 07:25, 3 May 2021 (UTC)

In general, there are three different ways to have multiple copies/versions/instances of the exact same file contents:

1. You can make a copy.
2. You can make a hard link. Two (or more) hard links reference one actual file, and there's no difference between the links: you can't say which is the "real name" and which are the "links".
3. You can make a symbolic link. A symbolic link is a reference from one name to another file, except in this case you can clearly say that the "real" file has its own name, and the symbolic link is just a link.

You can make a copy, or either kind of link, in the same directory as the original, but it must obviously have a different name. You can make a copy, or (usually) either kind of link, in a different directory than the original, and in that case it can have either the same or a different name. (The only thing you can't generally do is make a hard link in a different directory, but where that different directory is part of a different parent filesystem.) Steve Summit (talk) 15:53, 3 May 2021 (UTC)

A file is not in a directory, the directory contains a pointer to the file's details in filesystem's internals. Under *NIX this is to the index-node (inode), under FILES-11 it is to INDEXF.SYS. The inode (or whatever) describes the file's location on disk. A hard link is simply a file name and a pointer to the inode. Consider the index at the back of a book; there is no problem with having "Files, hard links" and "Hard links (filesystem)" pointing to the same page. Martin of Sheffield (talk) 16:52, 3 May 2021 (UTC)

Resolved

Thanks everyone. Bubba73 ^{You talkin' to me?} 14:19, 4 May 2021 (UTC)

Cloak of griffin

Hello there, I was recently reading an IT book, and was wondering is the cloak of griffin a legitimate thing (a way to bypass various filters. And controls that are set up) thanks Aiden LaBonne, That One Strange Child,⚔️🗡🔪 Memerman69 18:58, 3 May 2021 (UTC)

It was a purely fictional plot device in Stephen King's fantasy novel The Institute, named after the fictional character Griffin, the protagonist of H. G. Wells' novel The Invisible Man. Are there other uses of the term?  --Lambiam 20:44, 3 May 2021 (UTC)

I had never heard of it, and a quick google search revealed only mentions of The Institute, as well as this Quora post, which looks relevant. :-) —Steve Summit (talk) 20:55, 3 May 2021 (UTC)

That quora post (which I looked at) is relèvent and says pretty much the same. And as far as I know there are no other terms, ( I did a lot of research like half an hour later after asking the question) Thanks for the quick response, Aiden LaBonne, That One Strange Child,⚔️🗡🔪 Memerman69 14:16, 4 May 2021 (UTC)

It sounds like something that might happen in Family Guy. --Redrose64 🌹 (talk) 16:41, 4 May 2021 (UTC)