scripting_course VS coreutils

I'm still on Vim 8.1 (Ubuntu 20). Most of my settings are available here: https://github.com/learnbyexample/scripting_course/blob/master/.vimrc

Here's mine: https://github.com/learnbyexample/scripting_course/blob/master/.vimrc

I wrote ebooks on CLI one-liners based on grep/sed/awk/perl/ruby/coreutils/etc. These are free to read online: https://github.com/learnbyexample/scripting_course#ebooks

Plenty of examples and exercises.

There are huge lists on freely available books on programming topics here:

* https://ebookfoundation.github.io/free-programming-books/boo...

* https://ebookfoundation.github.io/free-programming-books/boo...

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All my book are free to read online and markdown source are available on GitHub: https://github.com/learnbyexample/scripting_course#ebooks

I did have an option couple of years back, but there were hardly any buyers. So I closed that store instead of spending time in keeping them updated.

All my books are free to read online: https://github.com/learnbyexample/scripting_course#ebooks

Also, you could print to pdf using the markdown source from my GitHub repos or use tools like pandoc to convert markdown to pdf/epub.

These might help:

* https://blog.sanctum.geek.nz/series/unix-as-ide/

* https://themouseless.dev/

Personally, I use gvim for all my text editing needs and use a normal terminal (i.e. no tmux, i3, etc). There's not much to share, unless you are interested in my vimrc, aliases, etc: https://github.com/learnbyexample/scripting_course

Thanks, do you mean web versions of my books? I made those using mdBook to convert markdown to html (plus js for things like search features).

https://github.com/learnbyexample/scripting_course#ebooks - I have several books on regex with plenty of examples/exercises (free to read online)

I have separate books for Python/Ruby/JS regexp. My books on grep/sed/awk include detailed chapters on regexp. You can read them for free online, see https://github.com/learnbyexample/scripting_course#ebooks for links. I use lots of examples to present a concept and there are plenty of exercises to test your knowledge as well.

I have a few resources collected here: https://github.com/learnbyexample/scripting_course/blob/master/Linux_curated_resources.md#shell-scripting

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" :)