Re: [9front] [PATCH] Kill, kill, slay: banish sed, long live awk!

[Amavect <amavect@gmail.com>]

On Sun, Jul 2, 2023 at 2:46 AM sirjofri <sirjofri+ml-9front@sirjofri.de> wrote:
>
> Hello,
>
> out of curiosity, why s/sed/awk? What's wrong about sed?
>
> sirjofri

The command line arguments are passed to sed through a sed expression,
so the program name is parsed as a sed expression and not as a string.
This affects program names with a dot (6.out).
In practice, this almost never results in name conflicts,
so the real reason is that I find the sed version hard to read.

For fun, I rewrote the sed version, which makes the command generation obvious:
ps | sed -n '/^'$user' .* '$i'$/s%[^ ]* *([0-9]+) .* (.*)$%@{echo
kill>/proc/\1/note} # \2%p'
Compare to the original:
ps | sed -n '/^'$user' .* '$i'$/s%[^ ]*  *%~>/proc/%s%  *.*
(.*)%/note} # \1%s%~%@{echo kill%p'
Compare to awk:
ps | awk -v 'user='$user -v 'prog='$i '$1 == user && $7 == prog {print
"@{echo kill>/proc/" $2 "/note} # " $7}'

Thanks,
Amavect