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From: "João Eiras" <joao.eiras@gmail.com>
To: cygwin@cygwin.com
Subject: Why is stdin always a pipe?
Date: Fri, 20 Jul 2018 13:17:00 -0000	[thread overview]
Message-ID: <CAJ+sA06u+pfPpTeFDQYaaT52c5_yz98i+MaTH28DCJoZkVc7=g@mail.gmail.com> (raw)

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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             reply	other threads:[~2018-07-20 12:03 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-20 13:17 João Eiras [this message]
2018-07-20 14:52 ` David Macek
2018-07-20 15:12   ` João Eiras
2018-07-21  0:59     ` Brian Inglis
2018-07-21  1:59       ` Heavenly Avenger
2018-07-21  2:31         ` João Eiras

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