Talk:Unix file types

What's a mode string?

This page mentioned "mode string" for several times. What's a mode string? Yegle (talk) 18:11, 11 February 2014 (UTC)[reply]

At the time of this writing, mode string are explained at Unix_file_types#Mode string. And at File system permissions. — Preceding unsigned comment added by 80.246.139.246 (talk) 23:54, 23 June 2020 (UTC)[reply]

What does this first sentence mean?

What does this first sentence mean? Being the well known entity files are, files are also called "regular files" to ... — Preceding unsigned comment added by 2606:6000:6042:6A00:6C2F:37B:43D5:28F4 (talk) 21:23, 2 November 2014 (UTC)[reply]

Proposed merge of Modes (Unix) into Unix file types

Both parts of "mode" as defined in the stat member is covered by this article. The representation is redundant with File system permissions#Traditional Unix permissions Artoria 2e5 🌉 12:49, 29 June 2020 (UTC)[reply]

@Artoria2e5: You proposed the merge at 12:49, 29 June 2020, and then two minutes later (at 12:51) you redirected the page to Unix file types#Representations. That hardly allowed any time for discussion.

You missed the earlier discussion at Talk:Modes (Unix)#Should this redirect to chmod? wbm1058 (talk) 01:14, 26 December 2020 (UTC)[reply]

wbm1058, apologies for the fast merge. I happened to decide on writing something about representation with sources, and it then occured to me that it already subsumes the mode thing. Mode being unreferenced, I thought nobody is gonna miss it. --Artoria 2e5 🌉 04:40, 26 December 2020 (UTC)[reply]

What does "Unix-based" mean?

This article uses the term "Unix-based" twice in the lead. What does it mean?

If it means "based on AT&T's Unix implementation", then it doesn't include, for example, most Linux distributions, with an independently-developed kernel and independently-developed userland software, even though Linux has the same notion of file types that AT&T Unix does, albeit perhaps with additional file types (just as systems based on the AT&T code have added file types).

If it means "Unix-compatible" or (mostly or totally) POSIX-compatible, that's pretty much the modern sense of Unix-like. (When I first heard the term, back in the late 1970s or early 1980s, it referred to reimplementations from scratch that may have had some incompatible API differences from Real Unix(TM). Those systems have largely either disappeared or removed the incompatibilities, and the term has pretty much come to mean systems such as Linux.)

The term is used in other articles as well; the same question applies there. Guy Harris (talk) 23:24, 6 September 2025 (UTC)[reply]

I think the intention was "Unix-like", so I went ahead and changed it. The cited section in Unix Power Tools says Recent versions of Unix (such as Linux), which is obviously wrong, so we're freewheeling here ;) — W.andrea (talk) 02:27, 7 September 2025 (UTC)[reply]

It's unclear to me whether a real UNIX (branded?) is classified as UNIX-like. Often I see text like "UNIX and UNIX-like" as if they are two distinct categories. Therefore, I don't use UNIX-like if I want the refer to things including real UNIX. UNIX-based seems to mean: squawks like a duck so it's a duck. I think it's a stretch to infer that based implies a codebase lineage. Software can be based on other software without having codebase lineage. Digging deeper: chatgpt assures ;) me that UNIX-like does include real UNIX. The Unix-like article kinda dances around the point which is why I avoid using that term unless I mean non-UNIX. If we think that UNIX-like includes real UNIX, then using that instead of UNIX-based does seem good. Further the Unix-like article should clearly state this aspect. Stevebroshar (talk) 12:55, 27 November 2025 (UTC)[reply]

It's unclear to me whether a real UNIX (branded?) is classified as UNIX-like. A dog is extremely dog-like. I see no problem with classifying a "UNIX", however "UNIX" is defined, as being "UNIX-like".

But there are multiple ways of defining "Unix"/"Unix":

branded UNIX, i.e. "it passed the Single UNIX Specification test suite, so the trademark 'UNIX' may be used when referring to it";
based on AT&T code, which raises the question "how much of the AT&T code on which it's purportedly based remains";
has APIs and commands that pretty much behave the way UNIX APIs and commands behave, but 1) that's a bit vague and 2) might just be what "Unix-like" means;
maybe others.

The nice thing about "branded UNIX" is there's a solid criterion for it (and at least two Linux distributions qualified before the SUS certification expired, so it serves the useful purpose of getting in the way of categorical "Linux is not Unix" statements.

I tend to use "UNIX"/"Unix" for branded UNIX and "Unix-like"/"UN*X" for everything else.

As for "Unix-based", what aspect of "UNIX" is it based on when people use the term? The APIs and commands, or the code? Guy Harris (talk) 11:33, 28 November 2025 (UTC)[reply]

Singular usually reads better than plural

Per revert comment: use optional plural since an OS may have one or multiple FS's.

"These types are used in the file system(s)" is not wrong, but "These types are used in a file system" reads better.

Yes. An OS can have multiple file systems. But that is not important for this article. This article is about types of files. That concept applies to a file system. Has nothing to do with how many file systems an OS has. If the concept of file type depends on how many file systems an OS has, then I don't understand file types. Stevebroshar (talk) 12:34, 27 November 2025 (UTC)[reply]

My main reason for editing was that you didn't explain all the changes you made, but I'm flexible on the wording.

"A file system of a Unix or Unix-like operating system" sounds weird to me, but I can't put my finger on why. I think it's because it implies that an OS can have no FS, even though obviously that doesn't make technical sense. Maybe it's just me.

Maybe some third option for the wording would be best, but I can't think of another way to phrase it.

Lastly, minor points just to clarify:

But that is not important for this article.
Yes, that's true. It's just a passing detail to mention for learners, but not relevant or even terribly important.
If the concept of file type depends on how many file systems an OS has, then I don't understand file types.
Yeah, don't read that much into it :)

— W.andrea (talk) 14:46, 27 November 2025 (UTC)[reply]

"A file system" on the machine on which I'm typing this could be HFS+ or APFS or VFAT or ISO 9660 (if I plug a CD drive into it or mount an ISO image) or UDF (if I plug a DVD drive into it or mount a UDF image) and so on. And it has multiple file systems mounted.

So I see no problem with speaking of "a file system" on that machine - it could be the root file system or /System/Volumes/Data or /Volumes/Case-sensitive or /Volumes/KINGSTON (if I've plugged one of my flash drives in) or.... Guy Harris (talk) 11:44, 28 November 2025 (UTC)[reply]

I know what a file system is and how they work; I'm saying the grammar/semantics sounds weird in the context of "These types are used in a file system of [an operating system]". — W.andrea (talk) 12:59, 28 November 2025 (UTC)[reply]