[9fans] bringing down vacfs in p9p

[9fans] bringing down vacfs in p9p

[Eoghan Sherry]

I can't figure out how to gracefully stop vacfs (or any other
file server for that matter) in p9p.

In plan 9 I can do an rm /srv/vacfs.test which immediately
removes the file causing vacfs to exit.

It'd be nice if rm `{namespace}^/vacfs.test would do the
same in p9p but it doesn't since unix won't remove the socket file
until vacfs closes it. I've resorted to 9 kill vacfs | rc
which doesn't seem right.

Is there something I'm missing? Is kill not that bad?

eoghan

[9fans] bringing down vacfs in p9p

[erik quanstrom]

the unix domain sockets in `{namespace} don't need to be removed;
9pserve -- not vacfs -- creats the socket file. it is not removed,
regardless of how things exit.

since vacfs doesn't do rfork(RFNOTEG), hitting delete in the 9term
window from which vacfs was started should kill vacfs off.

i don't see how that could be dangerous since vacfs is only a cache.

- erik

"Eoghan Sherry" <ejsherry@gmail.com> writes

|
| I can't figure out how to gracefully stop vacfs (or any other
| file server for that matter) in p9p.
|
| In plan 9 I can do an rm /srv/vacfs.test which immediately
| removes the file causing vacfs to exit.
|
| It'd be nice if rm `{namespace}^/vacfs.test would do the
| same in p9p but it doesn't since unix won't remove the socket file
| until vacfs closes it. I've resorted to 9 kill vacfs | rc
| which doesn't seem right.
|
| Is there something I'm missing? Is kill not that bad?
|
| eoghan

Re: [9fans] bringing down vacfs in p9p

[Russ Cox]

> In plan 9 I can do an rm /srv/vacfs.test which immediately
> removes the file causing vacfs to exit.

This is only true if vacfs is not mounted anywhere.
If someone's using it, removing the srv file won't
make vacfs exit.  Vacfs exits when reading from its
9P pipe returns eof.  That happens on Plan 9 when
all references to the other end of the pipe have
gone away.

> It'd be nice if rm `{namespace}^/vacfs.test would do the
> same in p9p but it doesn't since unix won't remove the socket file
> until vacfs closes it. I've resorted to 9 kill vacfs | rc
> which doesn't seem right.
>
> Is there something I'm missing? Is kill not that bad?

Kill is not that bad.  If you wanted to simulate Plan 9
and force an eof on the 9P pipe, you could kill the
appropriate 9pserve.

I can't think of any file servers that need to be shut
down gracefully on p9p except acme (which has an
Exit command).

Russ