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Posix Has Become Outdated (2016) [pdf]

cs.columbia.edu

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Re: Posix Has Become Outdated (2016) [pdf]

#81

Post by icebraining »

notalaser wrote: post #52
gaius wrote: post #41

Earlier quoted context omitted.

who thought Windows would replace Unix Windows now runs all the workloads that Sun, SGI, DEC, HP, IBM yadda yadda workstations once ran. I don't remember the last time I saw a real Unix workstation outside my home office where I keep an Octane for nostalgia's sake, and the wife has her old SPARCstation. But you are right about C and POSIX.

Let me paint this in a more interesting colour: at $work, most of our development work is very POSIX-y software (it only runs on Linux, but historically, at least portions of it used to run on a bunch of BSDs, too, and they probably still do, but no one tried it in years). Almost no one in the office uses Unix on their computer, not even those of us who use Linux at home. Most of us have Windows stations. We can inst…

I used to run Linux at my previous $workplace, but I definitely lost more time than my employer would be comfortable knowing disentangling things that regularly broke after updates

Sounds like you were upgrading too often (almost sure, if you were already dealing with systemd). Windows releases a new version only every 3-4 years, there's no reason to update your Linux workstations any faster. At my work, we're still using a mix of Ubuntu 12.04 and 14.04, both of which are still supported, and we just add a couple of repositories for specific applications (particularly browsers).

I do use Debian Unstable on my personal laptop, but that's because I don't mind fixing it if I have to (which, mind, I haven't had to do in a long time). But for work? LTS all the way.

Re: Posix Has Become Outdated (2016) [pdf]

#82

Post by JdeBP »

jstimpfle wrote: post #77
jonathankoren wrote: post #10

Sometimes I wish ACLs were better supported.

Who has put ACLs to good use anyway? Even the old model usually forces one to overspecify one's intent. It's too easy to shoot in your foot, and too hard to figure out what you need in the first place. I doubt there is a good general purpose permission model that's more complex than Unix modes. Collaboration on filesystems just doesn't work very well. It could work for many small groups if files had no users associat…

Well, for starters there are every Windows NT system you have ever used, which uses ACLs quite successfully and extensively for a whole host of reasons, and ... me. I put ACLs to good use myself.

Your wording, speaking of repositories and git, bespeaks a too-narrow idea of what ACLs can be used for. Aside from all of the examples that one can glean from Windows NT, from window stations to the trusted installer, there are things like using ACLs to govern access to in-filesystem control/status APIs, or using them to limit the things that a subverted logging daemon could possibly do.

Re: Posix Has Become Outdated (2016) [pdf]

#83

Post by tedunangst »

pjmlp wrote: post #24
cperciva wrote: post #18

The original goal of the POSIX standard was application source code portability. However, modern applications are no longer being written to standardized POSIX interfaces. Speak for yourself.

Try to write a modern iOS, OS X, Windows, Android, ChromeOS UWP with standardized POSIX interfaces .

Alright, so when did posix become outdated? Was it outdated 20 years ago because you couldn't write a Symbian app with standard posix interfaces?

Re: Posix Has Become Outdated (2016) [pdf]

#84

Post by rleigh »

LukeShu wrote: post #26
ndesaulniers wrote: post #22

Earlier quoted context omitted.

Isn't that what SELinux is for when they say it's Mandatory Access Control? Or are those two different things?

MAC and ACL are two different things. On Linux, ACL is the "facl" family of functions functions (and the set/getfacl programs). These supplement the traditional owner/group and mode bits. Essentially, it allows you to set a separate set of read/write/execute bits on a file for an arbitrary number of specific users or groups, rather than being limited to simply "owner", "group", "everyone-else". If anything is set bey…

Linux supports POSIX.1e DRAFT ACLs. These are a de-facto standard by implementation, but were never formally standardised by POSIX. They are also supported by other kernels.

However, other systems support the more modern and featureful NFSv4 ACLs. NFSv4 ACLs are supported by the NFSv4 filesytem and also used by ZFS. They are part of the NFSv4 formal specification. On systems supporting ZFS (other than Linux), you get the full NFSv4 ACL support. Linux doesn't have VFS support for NFSv4 ACLs, and doesn't expose them even for NFSv4 mounts. In contrast, a FreeBSD mount of an NFSv4 filesystem served from ZFS exposes the full permissions model to the client. FreeBSD has a separate set of richer acl_* functions rather than the get/setfacl functions on Linux.

Linux:

  % getfacl ~/.zshrc 
  getfacl: Removing leading '/' from absolute path names
  # file: home/rleigh/.zshrc
  # owner: rleigh
  # group: rleigh
  user::rw-
  group::r--
  other::r--
FreeBSD:

  % getfacl ~/.zshrc 
  # file: /home/rleigh/.zshrc
  # owner: rleigh
  # group: rleigh
              owner@:rw-p--aARWcCos:-------:allow
              group@:r-----a-R-c--s:-------:allow
           everyone@:r-----a-R-c--s:-------:allow
Linux really needs to get proper support for NFSv4 ACLs.

Re: Posix Has Become Outdated (2016) [pdf]

#86

Post by gkya »

pjmlp wrote: post #24
cperciva wrote: post #18

The original goal of the POSIX standard was application source code portability. However, modern applications are no longer being written to standardized POSIX interfaces. Speak for yourself.

Try to write a modern iOS, OS X, Windows, Android, ChromeOS UWP with standardized POSIX interfaces .

What? Those are not even POSIX environments (well, their primary and intended interface interface is not POSIX, but they maybe eventually inherit some of it because of their underlying environment or Unix influences, but that's irrelevant). Also, I never used OS X but AFAIK many Unix software runs on it easily, so it must be mostly compliant if not completely (IIRC it's a certified Unix).

Re: Posix Has Become Outdated (2016) [pdf]

#87

Post by gkya »

gm-conspiracy wrote: post #64
tmalsburg2 wrote: post #57

Earlier quoted context omitted.

Counter example: Almost everyone uses the Apache webserver when they browse the web, but hardly anyone even knows what that is. We could easily compile a long list of similar crucial infrastructure software that virtually everyone is using and that doesn't have graphical user interfaces.

Almost everyone uses the Apache webserver when they browse the web No. https://news.netcraft.com/archives/category/web-server-surve...

Nitpicking 101.

Re: Posix Has Become Outdated (2016) [pdf]

#88

Post by JdeBP »

coldtea wrote: post #73
AnonymousPlanet wrote: post #63

Earlier quoted context omitted.

At the end of the 80s and throughout the 90s, a common belief was that the CLI could be completely replaced by the GUI, one just hadn't yet figured out how. The GUI, however, never delivered those last 10-20% that you need in automation or in a context that requires reproducibility. Windows NT was designed towards those promises, but eventually Microsoft realised their mistake and created - ten years ago - Powershell…

> At the end of the 80s and throughout the 90s, a common belief was that the CLI could be completely replaced by the GUI And it has, except for backend programmers. Most Windows programmers stay all day in Visual Studio and the like, for example. But as far as end users as concerned, that is the 99% of computer users, the CLI might as well not exist.

I doubt that there is anyone at all in this entire discussion that can state with authority what "most Windows programmers" do. We can point to what we and the people we have met and talked to about this do, but to go from that comapratively scant few handsful of people to a statement the size of "most windows programmers" is an overgeneralization by several orders of magnitude.

Re: Posix Has Become Outdated (2016) [pdf]

#89

Post by johannes1234321 »

gkya wrote: post #86
pjmlp wrote: post #24

Earlier quoted context omitted.

Try to write a modern iOS, OS X, Windows, Android, ChromeOS UWP with standardized POSIX interfaces .

What? Those are not even POSIX environments (well, their primary and intended interface interface is not POSIX, but they maybe eventually inherit some of it because of their underlying environment or Unix influences, but that's irrelevant). Also, I never used OS X but AFAIK many Unix software runs on it easily, so it must be mostly compliant if not completely (IIRC it's a certified Unix).

That's exactly the point of the report: Hardly anybody uses POSIX. Many people use frameworks on top of it though. If POSIX would go away many won't notice.

Re: Posix Has Become Outdated (2016) [pdf]

#90

Post by JdeBP »

bluejekyll wrote: post #75
quickben wrote: post #72

Earlier quoted context omitted.

Arguably, you listed the projects that went out of their way heavily to restrict and lock-in users.

Isn't the point that those are the most prolific platforms, where a common API to the system, POSIX, would be most beneficial to us as developers? But it's simply not possible to do? From what I can tell POSIX has been replaced by per language stdlibs, with the portability of your software tied to the portability of a languages stdlib. POSIX was mainly designed for C, most other languages have a higher level abstract…

POSIX wasn't designed, per se. It's a standard, a lot of which was the codification of existing practices on operating systems where the C language was the primary language.

Also note the existence of FORTRAN language bindings, and the low level but persistent rumbles about C++ language bindings that have continued for the past 20 years or so.

Then note the number of languages where the doco tells you all about how "we wrap the C library", but what is actually there is in effect a language binding for POSIX for that language.

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