From owner-freebsd-arch@FreeBSD.ORG  Wed Jun  1 11:23:37 2005
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Date: Wed, 1 Jun 2005 21:23:23 +1000 (EST)
From: Bruce Evans <bde@zeta.org.au>
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Cc: freebsd-arch@freebsd.org
Subject: Re: [PATCH RFC] Add a macro for null mount options to sbin/mount*
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On Wed, 1 Jun 2005, Xin LI wrote:

> In our mount* utilities, the null mount option, which is usually be used
> as a terminator of an option vector, is defined with some hand-rolled
> terms, e.g.: {NULL}, {NULL, 0, 0, 0}, etc.

"{ NULL }" is the documented way.  See getmntopts.3.

> I think it would be nice to have a new macro to deal with this, say,
> MOPT_NULL, which would be extended to {NULL, 0, 0, 0}, which can act as
> an explicit initialize.  And in my opinion, something like:
>
> %%%
> opt = {
> 	MOPT_STD,
> 	MOPT_NULL
> };
> %%%

MOPT_NULL is a poor name.  It is not a null option, but a terminator that
happens to have nulls in it.

Bruce