linux VS coreutils

These are a bit easier to see what's going on:

https://github.com/torvalds/linux/commit/d5cf50dafc9dd5faa1e...

https://github.com/torvalds/linux/blob/d5cf50dafc9dd5faa1e61...

Unfortunately Github doesn't have a way to render symbols for whitespace, but you can tell by selecting the spaces that the previous version had leading tabs. Linus changed it so that the tokens `default` and the number e.g. `12` are also separated by a tab. This is tricky, because the token "default" is seven characters, it will always give this added tab a width of 1 char which makes it always layout the same as if it were a space no matter if you use tab widths of 1, 2, 4, or 8.

There was also a Gentoo effort to run atop FreeBSD[0]. The challenge of course is that afaik none of the BSD kernel ABIs are considered stable. The stable interface is the BSD libc. That said, with binfmt_misc, I don't see a reason you couldn't just run (at least some) FreeBSD binaries on Linux with a thin syscall translation layer (rather something like qemu-system) and then your layer hooked via binfmt_misc. I'm not aware of anyone who has done this for FreeBSD, but prior efforts existed as alternate binfmts for SysVr4/5 ELF binaries[2]. Either way would take some elbow grease, but you *might* even be able just reuse binfmt_elf and just have a new interpreter for FreeBSD elf.

[0] https://wiki.gentoo.org/wiki/Gentoo_FreeBSD

[1] https://docs.kernel.org/admin-guide/binfmt-misc.html

[2] https://github.com/torvalds/linux/blob/master/fs/binfmt_elf....

> The original less-than check was deemed incorrect

It was only deemed incorrect because of an information leak. Not because it's a valid use-case for user space to copy smaller portions of *hwrpb into user space. https://github.com/torvalds/linux/commit/21c5977a836e399fc71...

Correct. And the combined work needs to carry the MIT license text and copyright attributions for the MIT software authors. With binary distribution it must also be overt, not hidden in some source code drop, but directly accompanying the binary.

Many people who talk about relicensing never credit the MIT developers or distribute the MIT license text. "Because it's GPL now."

I don't think that you believe that, but many developers do.

Some don't see the need for source code scans for Open Source compliance, because the license.txt says GPL, so it's GPL. Prime example is the Linux kernel. There is code under different licenses in there, but people don't even read https://github.com/torvalds/linux/blob/master/COPYING till the end ("In addition, other licenses may also apply.") and conclude it's simply GPL 2 and nothing else.

Also be aware that sublicensing is not the same as relicensing.

> Does he have something against it?

He notoriously hates GNU Emacs, yes.

https://marc.info/?m=122955159617722

https://github.com/torvalds/linux/blob/master/Documentation/...

So If we would only count code and not comments, it is only 9489 LoC Rust. Which would be about 0.03% and if we take all lines and not only LoC it would be around 0.05%

[0] https://github.com/XAMPPRocky/tokei

[1] https://github.com/torvalds/linux/commit/b401b621758e46812da...

AIUI fsync is built on futex_waitv which has been upstreamed. So this has to be more than that.

https://github.com/torvalds/linux/commit/a0eb2da92b715d0c97b...

git clone --no-checkout --depth 1 https://github.com/torvalds/linux.git $dir

https://github.com/coreutils/coreutils/commit/fcfba90d0d27a1...

A summary of other changes just released in GNU coreutils 9.5 are:

* mv accepts --exchange to swap files

> some are simple like yes(1)

Not that simple: https://github.com/coreutils/coreutils/blob/master/src/yes.c

The -S / --split-string option[1] of /usr/bin/env is a relatively recent addition to GNU Coreutils. It's available starting from GNU Coreutils 8.30[2], released on 2018-07-01.

Beware of portability: it relies on a non-standard behavior from some operating systems. It only works for OS's that treat all the text after the first space as argument(s) to the shebanged executable; rather than just treating the whole string as an executable path (that can happen to contain spaces).

Fortunately this non-standard behavior is more the norm than the exception: it works at least on modern GNU/Linux, BSDs, and macOS.

[1] https://www.gnu.org/software/coreutils/manual/html_node/env-...

[2] https://github.com/coreutils/coreutils/blob/b09dc6306e7affaf...

> building a cat from scratch

> That would be an interesting project.

Here is the source code of the OpenBSD implementation of cat:

> https://github.com/openbsd/src/blob/master/bin/cat/cat.c

and here of the GNU coreutils implementation:

> https://github.com/coreutils/coreutils/blob/master/src/cat.c

Thus: I don't think building a cat from scratch or creating a tutorial about that topic is particularly hard (even though the HN audience would likely be interested in it). :-)

the yes command, writing to /dev/null, is making IO calls, which interfere with predictable scheduling.

If you look at the source code for yes, https://github.com/coreutils/coreutils/blob/master/src/yes.c

it builds a buffer of output and then writes that in a for loop

  while (full_write (STDOUT_FILENO, buf, bufused) == bufused)

Looking at the source of nohup, if the execvp() of the child happens then it _must_ have already done the signal (SIGHUP, SIG_IGN) so - WTF?

This got me wondering so I went and looked and it seems like lo and behold there was actually a commit to the GNU ls source just 2 weeks ago.

https://github.com/coreutils/coreutils/blob/master/src/ls.c

"maint: prefer char32_t to wchar_t"

even an empty file? Yes. so now it was a file with a copyright disclaimer and nothing else. And the koan-like question comes to mind is "Can you copyright nothing?" well AT&T sure tried.

Then somebody said our programs should be well defined and not depend on a fluke of unix, which at this point was probable a good idea. so it became "exit 0"

Then somebody said we should write our system utilities in C instead of shell so it runs faster. openbsd still has a good example of how this would look.

http://cvsweb.openbsd.org/cgi-bin/cvsweb/~checkout~/src/usr....

At some point gnu bureaucracy got involved and said all programs must support the '-h' flag. so that got added, then they said all programs must support locale so that got added. now days gnu true is an astonishing 80 lines long.

https://github.com/coreutils/coreutils/blob/master/src/true....

http://trillian.mit.edu/~jc/humor/ATT_Copyright_true.html

> Yes, ls is maintained. Although, maintained is a very strong word. It exists.

Why would it be a strong word? Here it is, in src/ls.c: https://github.com/coreutils/coreutils

It is then packaged by tens of operating system distributions, who themselves maintain extra patchsets, some of which are then upstreamed.

It is installed and used on millions (billions?) of devices, for 3 decades.

It's a very reliable and trusty "sharp stick of metal" :)