Re: PROPOSAL: /proc/dev (new idea)

Patrick St. Jean (psj@cgmlarson.com)
Thu, 1 Jan 1998 12:03:11 -0600 (CST)

On Thu, 1 Jan 1998, linux kernel account wrote:
> How about modifying mount so that it can pass an approiate config file to
> devfs. There would then need to be some procedure to write back this
> config file if /dev is modified.
>
> OR
>
> When devfs is mounted on /dev. It assumes it's default settings (however
> you do that) and then it peaks into /dev on the root fs. It then copies
> whatevers there on top of it's current configuration (it would be there
> just as standard dev files. Whenever someone modifies or creates a /dev/
> file or symlink the deffs could writeback the change to the rootfs /dev..

After I finished writing that I though of an idea... Say you have default
permissions, etc. on the files in this devfs. When it is mounted, all the
devices show up with those default permissions. You put a file in /etc
that has some specialized information (name, permission, ???) and run a
devconfig binary that calls a kernel function to update the permissions...
That can be done at boot in an rc script and then later when the admin
decides to change it. Simple, non-cluttering, program that you don't
need to run at all unless you change something.

I'll have to disagree with you on the whole symlink thing for one simple
reason... The root fs (IIRC) can be any number of different REAL
filesystem types, and handling all of them would be just a big pain in the
butt... Lets just ditch the whole "on disk" filesystem idea and make it
all in "virtual" space linke /proc.

> I really see a need for such a beast though.. Lots of device activity
> keeps the hd spinning writing ctimes and atimes.. Also, can you imagine
> the inode wastage on a system setup to accept hundreds of ptys?

Yeah, which it seems to me is why having this as an overlay of a physical
/dev is not so good.

Best
Pat

-- 
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| Patrick St. Jean              '97 XLH 883                psj@cgmlarson.com |
| Programmer & Systems Administrator                    +1 713-977-4177 x115 |
| Larson Software Technology                        http://www.cgmlarson.com |
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