Re: Git branch outputs usage message on stderr

From: Matěj Cepl <mcepl@cepl.eu>
Date: Jan 15, 2025, 11:36 UTC
Message-ID: <D72M6S9O1E9F.WVEBV7ZJ1JTC@cepl.eu>
In-Reply-To: <04cfaa3b-847f-4850-9dd6-c1cf9f72807f@uni-muenster.de>

On Wed Jan 15, 2025 at 12:22 PM CET, Jonas Konrad wrote:

Show 6 quoted lines

> What did you do before the bug happened? (Steps to reproduce your issue)
> I opened a terminal on Arch Linux with a bash shell and called `git 
> branch -h` to get a usage overview of git's `branch` command. I then 
> tried processing the output with `grep` by `git branch -h | grep list` 
> which gave the whole (unfiltered) output, i.e., the displayed message 
> was not processed by `grep`.

And that is exactly the correct behaviour. In the world of UNIX, where pipes are normal, utilities should send to the stdout only substantial material, which could be processed down the pipeline. Error messages, help, and similar diagnostics, should go to stderr. Also, you know about `|&`, right?

Best,

Matěj

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