Network Character Device (NCD)?

Ric Werme ewerme at comcast.net
Tue Jul 10 17:34:01 EDT 2007


Ben Scott wrote:
On 7/10/07, VirginSnow at vfemail.net <VirginSnow at vfemail.net> wrote:
> > ... reads/writes/ioctls to /dev/ncd*, wrap them up in UDP ...
> 
>   TCP would be better for a character device, I would think, since
> character devices and TCP are both basically just a stream of bytes.

You also want to include open/close and keep the device open until its closed.
Otherwise you'd get interesting effects like tape drives rewinding after
each write.  Certainly with UDP, and possibly with TCP, something
would need to order the I/Os.  Even if you included the file offset in
each read or write, tapes don't suffer seeks gladly.

All that's one of the reasons why NFS doesn't really work with anything
but disk filesystems.

As for accessing character and block devices, if you want to just read or
write, rsh or ssh generally works.  Ioctls, of course, are not so simple.

       -Ric Werme


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