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Date: Thu, 8 Sep 2016 19:36:33 +0200
From: Jilles Tjoelker <jilles@stack.nl>
To: "Lundberg, Johannes" <johannes@brilliantservice.co.jp>
Cc: FreeBSD Current <freebsd-current@freebsd.org>
Subject: Re: Weirdness in TTY & VT
Message-ID: <20160908173633.GA50215@stack.nl>
References: <CAASDrVky8v4FWjqKYgv1mJ0-ksqVD9KWTNBNatfSVxBOBc5eyQ@mail.gmail.com>
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On Fri, Sep 02, 2016 at 05:12:12PM -0700, Lundberg, Johannes wrote:
> I'm porting some Linux code and have some weird behavior.

> In this (Linux) code fstat() and minor() is used on a /dev/tty file
> descriptor to get a tty number to map to. In FreeBSD this returns a number
> around 60-70 for st_rdev which means VT_ACTIVATE ioctl call will fail
> because it only allows values 0-12.

> Should not this be compatible with FreeBSD? If not, what is the FreeBSD way
> to do this?

> Is there some implementation missing in vt?

minor() and major() are obsolete in FreeBSD. A (userland) dev_t is an
opaque identifier.

The direct equivalent is devname_r() or fdevname_r() followed by parsing
the resulting string.

There is also a VT_GETINDEX ioctl but I don't know whether it works.

-- 
Jilles Tjoelker