Re: [9fans] Dir->type & Dir->dev

[erik quanstrom <quanstro@quanstro.net>]

On Sun Nov 30 10:12:00 EST 2008, ericvh@gmail.com wrote:
> The main pages are a little unclear as to the convention for
> assignment of dir->type & dir->dev, particularly with respect to
> synthetic file servers.  For devices I gather that type is the device
> id (ie. 'c' for cons) and that dev is the instance (ie. #I2 for an
> alternate IP stack).  Their use seems a bit more slippery when
> implementing user space file servers -- particular since type,dev,qid
> must(?) be unique per namespace.  Is there a best practices convention
> that folks follow or is this something which most ignore and we are
> just lucky most of the time?
>
>              -eric

there is a dir.type and a dir.qid.type.  i believe these are different.
the comment above dir.type in /sys/include/libc.h says that it's
system modified.  and, e.g. /mail/fs shows up as from the mount
driver.  the instance is typically pretty big.  the mount driver is
pretty careful to count instances.

; ls -l /mail/fs
--rw-rw-rw- M 105920 quanstro quanstro 0 Nov 30 10:17 /mail/fs/ctl
d-r-xr-xr-x M 105920 quanstro quanstro 0 Nov 30 10:11 /mail/fs/mbox

- erik