Re: [PATCH v2 3/4] terminal: work around macos poll() bug

From: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
To: Phillip Wood <phillip.wood@dunelm.org.uk>
Cc: Git Mailing List <git@vger.kernel.org>,
	Carlo Arenas <carenas@gmail.com>,
	Johannes Schindelin <Johannes.Schindelin@gmx.de>,
	Ramsay Jones <ramsay@ramsayjones.plus.com>
Subject: Re: [PATCH v2 3/4] terminal: work around macos poll() bug
Date: Thu, 10 Mar 2022 14:35:00 +0100	[thread overview]
Message-ID: <220310.86v8wmj5c8.gmgdl@evledraar.gmail.com> (raw)
In-Reply-To: <20220309110325.36917-4-phillip.wood123@gmail.com>

On Wed, Mar 09 2022, Phillip Wood wrote:

> From: Phillip Wood <phillip.wood@dunelm.org.uk>
>
> On macos the builtin "add -p" does not handle keys that generate
> escape sequences because poll() does not work with terminals
> there. Switch to using select() on non-windows platforms to work
> around this.
>
> Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
> ---
>  compat/terminal.c | 43 +++++++++++++++++++++++++++++++++++++------
>  1 file changed, 37 insertions(+), 6 deletions(-)
>
> diff --git a/compat/terminal.c b/compat/terminal.c
> index cb653419c3..4189cbb12c 100644
> --- a/compat/terminal.c
> +++ b/compat/terminal.c
> @@ -82,6 +82,32 @@ static int enable_non_canonical(enum save_term_flags flags)
>  	return disable_bits(flags, ICANON | ECHO);
>  }
>  
> +/*
> + * On macos it is not possible to use poll() with a terminal so use select
> + * instead.
> + */
> +#include <sys/select.h>

I don't think this breaks anything in practice due to the platforms we
define HAVE_DEV_TTY and NO_SYS_SELECT_H on, but it does look redundant &
confusing, and will break if the current users of HAVE_DEV_TTY and
NO_SYS_SELECT_H change.

I.e. isn't sys/select.h already pulled in by the relevant include in
git-compat-util.h? Why is it needed again here?