No_color: Disabling ANSI color output by default

by agvxov • 10 months ago

53 15 10 months ago

openmarkand• 10 months ago

Hmm, why not.

Though most of the software do the right thing by checking if the standard output is an actual tty (isatty) to avoid colors when redirecting to something else (e.g. socket, fifo, etc).

The name NO_COLOR suggests a really binary choice which may be okay. Though GNU coreutils usually have a more selective option like --color=always|auto|never.

I'd prefer supporting a more general COLORS=on|off|compatible|...

Meaning:

- on: always on even when redirecting

- off: fully off

- compatible: maybe something like on by default and off if redirecting to a non-tty

- ...: add more choices

sudahtigabulan• 10 months ago

Though most of the software do the right thing by checking if the standard output is an actual tty (isatty) to avoid colors when redirecting to something else (e.g. socket, fifo, etc).

NO_COLOR is orthogonal to the isatty suppression.

NO_COLOR ensures that colors are off even when stdout is not redirected.

For example, when you have poor vision, poor quality display, or sit near a window, (or worse – a combination of these) the colored parts of the output might have lower contrast, low enough to make them impossible to read.

cb321• 10 months ago

do the right thing by checking if the standard output is an actual tty (isatty)

This is a very questionable heuristic. I'm not sure the exact date that support began, but I have been piping color output to `less -r/-R` for decades. This can be nice even for less than multi-terminal-page output just for "search".

isatty(stderr) would actually be more accurate for my specific use cases for when I don't `|&` or maybe even `isatty(stdin)`, but those are also imperfect heuristics.

The point is, since "auto" is a questionable heuristic, it is not so crazy/wrong to just default to color-on and have an off switch and that off switch is what NO_COLOR is about (as explained by the very first sentence in the linked article). Desirable defaults ultimately depend upon the distribution of your user's tastes (as always, more|less).

yjftsjthsd-h• 10 months ago

Yeah, my first thought on seeing this was that I really want a way to force color just as easily; when I output diffs in CI, they're much more readable with color but it's a pain to enable it when running headless.

bhaak• 10 months ago

I'd argue that if somebody implements NO_COLOR support they will likely also implement a --color switch to force color.

At least I do. :)

blueflow• 10 months ago

Neither "curses" nor "ncurses" are mentioned on the page - that would be the traditional place to implement such behavior. terminfo still has xterm and xterm-color separately, so this functionality used to exist ($TERM based, tho) before go and rust.

antonyh• 10 months ago

Maven has the `-B` option, but that has the side effect of working in a no-input mode so it's not ideal. There's plenty of times I'd like to have it working interactively but without the ANSI colour codes.

lukasgelbmann• 10 months ago

Does NO_COLOR=1 mean that all ANSI formatting should be disabled? Including bold text, italic text, and so on?

It seems that different software handles that question in different ways.

willm• 10 months ago

I asked the author a while back. They said it purely relates to colour. Not other styles. Alas, they removed the issues and there is no record of that.

trashb• 10 months ago

Isn't there already a lot of separate implementations around color handling?

It would be good to unify it, perhaps some of the distributions can also have a hand in it.

terminfo also has "Mono mode" with the "-m" suffix which I don't see mentioned in the article.

I see a lot of handing of color options in the standard Ubuntu .bashrc https://gist.github.com/marioBonales/1637696

post_on_hn• 10 months ago

No, we need OS-wide setting to also change light mode and dark mode across GUI/TUI/console without restarting applications.

singularity2001• 10 months ago

export NO_COLOR=1

had no effect yet

aiiizzz• 10 months ago

The terminal _really_ sucks for UI. I wish it was better

esseph• 10 months ago

I couldn't disagree more.

lowlevel• 10 months ago

I have been disabling colour for 30 years… and it’s always a pain in the butt. Glad to see this acknowledged at least.

No_color: Disabling ANSI color output by default

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