From: Alexander Holler <holler@ahsoftware.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Mike Frysinger <vapier.adi@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/1] Implement /dev/byte (a generic byte source similiar to /dev/zero)
Date: Tue, 19 Apr 2011 11:05:10 +0200 [thread overview]
Message-ID: <4DAD5046.3030008@ahsoftware.de> (raw)
In-Reply-To: <20110419094436.0b667410@lxorguk.ukuu.org.uk>
Hello,
Am 19.04.2011 10:44, schrieb Alan Cox:
>> As for /dev/zero there are many other possible reasons to use such a
>> device, besides filling something with a value. For me it's as
>> reasonable as dev/zero, just that it offers a bit more flexibility and
>> provides another, at least for me useful, default value. Maybe
>> /dev/nzero would have been a good name too. ;)
>
> /dev/zero exists not to put \0's into files as such but because it is
> very useful to be able to map the zero page (a read only, or
> copy-on-write blank page) into programs. The mmap is the reason it is
> there.
Thanks for the explanation.
>> But I don't really care about inclusion into the kernel, it's just
>> something I had lying around (and needed only marginally work to
>> finalize as a proper patch) and I thought someone else could find it
>> usefull and I should share that here.
>
> Implementationwise I think I would have gone for allocating a new device
> and range of 256 minors - that would avoid the funky stuff setting what
> it fills with as you'd just fill with the minor number.
I thought about that too, but that would have been to easy (and static). ;)
And the usage of file descriptors was the only idea I've come up with,
which is multitasking and multiuser aware.
Regards,
Alexander
next prev parent reply other threads:[~2011-04-19 9:05 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-04-18 11:37 [PATCH 0/1] Implement /dev/byte (a generic byte source similiar to /dev/zero) Alexander Holler
2011-04-18 11:37 ` [PATCH 1/1] " Alexander Holler
2011-04-20 10:57 ` Pavel Machek
2011-04-20 18:07 ` Alexander Holler
2011-04-18 13:57 ` [PATCH 0/1] " Mike Frysinger
2011-04-19 8:34 ` Alexander Holler
2011-04-19 8:44 ` Alan Cox
2011-04-19 9:05 ` Alexander Holler [this message]
2011-04-19 9:32 ` Alexander Holler
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4DAD5046.3030008@ahsoftware.de \
--to=holler@ahsoftware.de \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=vapier.adi@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.