Re: NFS /etc/exports syntax

On Tue, Jan 20, 2026 at 05:47:21AM -0800, Rick Macklem wrote:
> On Mon, Jan 19, 2026 at 9:30 PM Steve Rikli <sr@genyosha.net> wrote:
> > There appear to be some inconsistencies in exports(5) man page, or at
> > least a couple things which have me wondering a bit.  :-)
> ...
> > Different but related, is there a syntax rule for "chaining" flags
> > together after a leading "-"?  E.g. is something like this valid:
> >
> >   /foo -maproot=root,ro,alldirs -network=1.2.3.4/24
>
> No, each flag must be separate with the "-" at the beginning of
> it, from what I can see. (The parsing code is literally decades
> old. It was first written in the late 1980s.)

Does that mean this line from EXAMPLES is actually invalid?

    /cdrom -alldirs,quiet,ro -network 192.168.33.0 -mask 255.255.255.0
             ^^^^^^^^^^^^^^
Note the "," between alldirs,quiet,ro flags, with no spaces or dashes.

> > From a readability standpoint, this seems clearer to me:
> >
> >   /foo -maproot=root -ro -alldirs -network=1.2.3.4/24
>
> Not sure what you were asking about this line, but it
> looks ok to me.

That example was simply to draw a comparison between "-flag1 -flag2" and
the above question about "-flag1,flag2". I find the clarity and
readability better with dashes and spaces between flags, vs. chaining
flags together with commmas.  $.02.

> > but I'm curious if there is a formal syntax definition for this stuff.
>
> Nope. It's very old C that has been hacked by many over the
> years. I can barely figure out what it is doing when I look at it
> and I've looked at it many times.

Understood. I'm guessing the very old C code is somewhat reflected in
the exports(5) content -- the man page has a lot of info, and some of it
resembles a proverbial wall of text. :-) The EXAMPLES are pretty
helpful, fortunately.

Thanks,
sr.