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From:	=?UTF-8?Q?Jo=C3=A3o_Eiras?= <joao DOT eiras AT gmail DOT com>
Date:	Fri, 20 Jul 2018 14:02:45 +0200
Message-ID:	<CAJ+sA06u+pfPpTeFDQYaaT52c5_yz98i+MaTH28DCJoZkVc7=g@mail.gmail.com>
Subject:	Why is stdin always a pipe?
To:	cygwin AT cygwin DOT com
X-IsSubscribed:	yes

Hi.

I'm trying to figure out the best way to detect when my program is
being piped data.

So far I've used in linux often "[[ -p /dev/stdin ]]". During an
interactive session, /dev/stdin will be a character device, not a
pipe, and if stdin is closed ( command 0<&- ) then it's nothing.

But in cygwin, /dev/stdin is ALWAYS a pipe. So, I could use "[[ -t 0
]]" to check if stdin is a tty, but that would not cover when running
my script in a background job or service with a closed stdin.

So, a) what is the correct way to detect if stdin is being piped data
and b) is this a bug or design limitation ?

Thank you.

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