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From: Peter Wemm <peter@FreeBSD.ORG>
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Date: Fri, 26 Sep 1997 05:57:30 -0700 (PDT)
Message-Id: <199709261257.FAA05030@freefall.freebsd.org>
To: uhclem@nemesis.lonestar.org, peter@FreeBSD.ORG, freebsd-bugs@FreeBSD.ORG
Subject: Re: kern/4628
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Synopsis: Device driver de won't accept "media" parameters to go Full Duplex:FDIV071

State-Changed-From-To: open-closed
State-Changed-By: peter
State-Changed-When: Fri Sep 26 05:42:01 PDT 1997
State-Changed-Why: 
If one modifies a shell script (such as /etc/rc.conf) one should
understand basic shell quoting.

One way might be to do something like this:
ifconfig_de0="mumble -media 'foo bar'"
or
ifconfig_de0='mumble -media "foo bar"'

The requirement is that the argument string presented to the -media
switch is a single argument.

To get the list of currently supported medias for a driver, use 'ifconfig -m'.

What you are probably after is:
ifconfig_de0="mumble media 10baseT/UTP mediaopt full-duplex"
(or s/UTP/BNC/)

Here, with a SMC9332BDT, the choices are:
supported media: autoselect 100baseTX <full-duplex> 100baseTX 10baseT/UTP <full-duplex> 10baseT/UTP

So, one can:  ifconfig de0 media 100baseT mediaopt full-duplex
to override the autoselect setting.