Not to mention that it is missing “good citizen” features like turning off colors when stdout is not a tty.
Is it actually the case?
The comment you cite says the code won't work on xterm or gnome-terminal.
I've checked with what I had available: XTerm(330) and GNOME Terminal 3.30.1 using VTE 0.54.1. On both terminals the last code sample from the post works perfectly fine as far as I can tell.
What terminal should I use to see improper behavior of the program?
Better solution: do not detect whether your output is a tty or not.
Let the user decide they want colors or not by using `--color=always` or `--color=never` or similar.
There's few things worse than writing a script and getting different output just because you're no longer running the program interactively.
> $ echo "{}" | jq > {} > $ echo "{}" | jq > out.json > jq - commandline JSON processor [version 1.5-1-a5b5cbe] ... etc ...
Turns out when stdout isn't a tty you _must_ specify a filter (in this case '.')
It happens all the time with anything systemd or networkmanager too
grep box file.txt
grep box file.txt | grep -v orange-box
grep --color=always orange-box file.txt
grep --color=always box file.txt | grep --color=always orange-box
And if I wanted to write that out to a file then I would do
grep --color=never orange-box file.txt > matches.txt
grep --color=always box file.txt | grep --color=always box | ansi2txt > no-color-matches.txtMaybe grep should ignore ansi sequences optionally or by default, to solve this?
It's a tutorial, not a 1000 page book. Some things won't be in there.
Besides, detecting stdout or tty isn't even relevant for interactive TUI applications.