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From: Malcolm Kay <malcolm.kay@internode.on.net>
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Date: Thu, 5 Jan 2006 14:24:37 +1030
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Cc: user <user@dhp.com>
Subject: Re: how can I find out which md device I just used ? (mdconfig)
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On Thu, 5 Jan 2006 01:50 pm, user wrote:
> mdconfig will use the next available md device, as long as you
> do not specify a particular device on the command line with
> the -u switch.
>
> Which is great.
>
> However, in a script, the very next thing I want to do is
> mount that mdconfig'd vnode filesystem.  But I do not know
> which md device mdconfig just used.
>
> I do not see any way in the mdconfig man page to get mdconfig
> to output what device it is using when it is invoked ...
>
> So ... assuming I am running mdconfig, followed by mount, in a
> shell script ... and I do not specify a device becuase i do
> not know what devices are available (beacuse I am running it
> automated) ... how can I find out (any suggestions
> appreciated) what md device just got used so I can mount it ?
>
> I consiudered running `mdconfig -l` before and after the
> mdconfig, and choosing the one that shows up as new, but that
> is not elegant and is vulnerable to a race condition.
>

On my system (5.4) mdconfig reports the created device to stdout:
So:
	memdevice=`mdconfig -a -t malloc -s10M`
sets the device name in $memdevice.

Malcolm Kay