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Comment by dexen | Hacker News Reader

UNIX Style, or cat -v Considered Harmful, http://harmful.cat-v.org/cat-v/ (see the linked PDF, http://harmful.cat-v.org/cat-v/unix_prog_design.pdf)

Another example: the modern Bash shell vs the Plan 9's Rc shell. The difference in documentation is over tenfold, with the latter still being more less laden with gotchas:

  $ man bash | wc -w
  48189
  $ 9 man rc | wc -w
  3264

Having said that, I still love me some sick diff -burN-style mnemonics.

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Thanks for the new addition to my mnemonic collection!

perl -lane # process input by line, split into fields, print outputs with new lines, execute code

netstat -planet # show process, extended info, all socket types

ss -pimento # basically every piece of info about live connections

iostat -txyz # extended, omit first report (the since-boot one), omit devices with no activity, log datetime

  less -SEXIER

Truncate long lines instead of wrap, quit at eof, don't clear the screen, show ansi color escape codes as colors but escape other ansi escape codes.

(The second E does nothing but complete the word)

Imagine an old PS/2 mouse with a mini Jack cord & plug. Non-standard but works. I mean, on GNU/Linux:

  ps aux

Party time:

  rsync -rave ssh SOURCE DESTINATION

I use -avz

Aww, shucks: rsync -aSHx src/ dest

The entirety of plan 9 cat is just 36 lines. That's true unix philosophy. Small tools that do one thing well which when combined produce more powerful tools. The -v flag is silly bloat as cat is nothing more than a program which catenates files.

  $ man dash | wc -w
  10122

If you are running scripts most of the time bash is overkill (batch files don't need things like command completion, history and all that interactive stuff). Don't believe me?

  $ ls -lAh `which bash`
  -rwxr-xr-x 1 root root 1.1M Jun  6  2019 /bin/bash

  $ ls -lAh `which dash`
  -rwxr-xr-x 1 root root 119K Jan 25  2018 /bin/dash

but rc doesn't have built in regex and doesn't have hash tables. My guess is that bash is trying to be a full scripting language these days, sort of like perl.

>but rc doesn't have built in regex and doesn't have hash tables

That's an advantage; Plan 9 provides awk for those use cases. There is a clear separation, and a simple yet powerful language for communication (pipes, file descriptors, and files).

>bash is trying to be a full scripting language these days

Arguably Bash over-did somewhere around the time they added support for TCP connections

  exec {FD}<>/dev/tcp/news.ycombinator.com/80; echo GET / >&$FD; cat <&$FD

Maybe there was a clear separation 30 years ago, but there no longer is. The shortcut for the posts below is that you can write a Lisp in all of shell, awk, and make (and sed too) [1]

I won't get to this in Oil (without help) but I still think it's valid. The languages have so much overlap that they should just be combined. Of course that's what Perl was (leaving out Make), but Raku and Python 3 seem to have left a hole in that design space.

Shell, Awk, and Make Should Be Combined http://www.oilshell.org/blog/2016/11/13.html

Example Code in Shell, Awk, and Make http://www.oilshell.org/blog/2016/11/14.html

[1] https://github.com/kanaka/mal/tree/master/impls

Actually, that's something that seems inspired by Plan 9 with its /net/tcp/xxx files. Bash just tries to make it cross platform so it cannot rely on the host OS like rc does.

There were already netcat and similar tools that worked together with bash to provide this functionality.

Not sure if arguing for plan9 simplicity by pointing out bashisms designed to emulate how one might use sockets on plan9/rc is the best strategy.

The difference being that such functionality arose from the fundamentals of how plan9 worked, whereas bash hacked in a simulacrum.

Because rc is a shell to run commands, hence the name rc, run command. For the tasks you mentioned you would use a program or language such as awk to handle those cases.

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