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From: dave@horsfall.org (Dave Horsfall)
Subject: [TUHS] Device special files
Date: Wed, 7 Feb 2018 16:39:08 +1100 (EST)	[thread overview]
Message-ID: <alpine.BSF.2.21.1802071628390.50080@aneurin.horsfall.org> (raw)
In-Reply-To: <20180207021405.CF19B156E812@mail.bitblocks.com>

On Tue, 6 Feb 2018, Bakul Shah wrote:

>> Wasn't that "devfs" (which Penguin/OS calls "udev")?  I've never 
>> grokked that concept.
>
> In the old days where a limited types of devices were
> available for a particular kind of machine, they could be
> statically assigned a major dev number (matching their index
> in the {b,c}devsw table). To make them accessible to users you
> did
>
>    mknod <name> <b or c> <major> <minor>

[...]

Umm, I've known that since Edition 5; I'm not exactly new to Unix, you 
know...

[...]

> So the point of devfs is to avoid having to do mknod manually and yet 
> provide access to all found devices from the userland. As a side effect 
> you can also use it for programs that run in their own sandbox or for 
> jails and require access to a device.

That makes sense; bit of a pain when a USB device suddenly disappears just 
I unplugged it, though...

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."


  reply	other threads:[~2018-02-07  5:39 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-06 15:56 ron minnich
2018-02-06 17:56 ` Larry McVoy
2018-02-06 18:03   ` ron minnich
2018-02-06 19:48 ` Random832
2018-02-07  1:25   ` Greg 'groggy' Lehey
2018-02-07  1:36     ` Ron Natalie
2018-02-07  1:40       ` Clem Cole
2018-02-07  1:47         ` Henry Bent
2018-02-07  1:48     ` Dave Horsfall
2018-02-07  2:06       ` Dan Cross
2018-02-07 16:24         ` Arthur Krewat
2018-02-07 16:34           ` Dan Cross
2018-02-07 16:34           ` Nemo
2018-02-07 16:59             ` ron minnich
2018-02-08  0:39           ` Dave Horsfall
2018-02-08 16:18             ` Arthur Krewat
2018-02-08 22:47               ` Dave Horsfall
2018-02-07  2:13       ` Bakul Shah
2018-02-07  5:39         ` Dave Horsfall [this message]
2018-02-07 18:36           ` Steffen Nurpmeso
2018-02-07 19:07             ` Ian Zimmerman
2018-02-07 22:05               ` Clem Cole
2018-02-07 22:38                 ` ron minnich
2018-02-07 22:48                 ` Ron Natalie
2018-02-08 18:59                   ` Random832
2018-02-07 23:06                 ` Bakul Shah
2018-02-08 19:06               ` Steffen Nurpmeso
2018-02-07 22:04             ` Dave Horsfall
2018-02-08 13:03               ` Rafael R Obelheiro
2018-02-08 19:25               ` Steffen Nurpmeso
2018-02-07  1:38 Noel Chiappa
2018-02-09  0:09 Doug McIlroy

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