Subject: sd: MEDIA_LOADED not reset on last close?
To: None <tech-kern@NetBSD.ORG>
From: Mark Brinicombe <>
List: tech-kern
Date: 05/06/1996 00:21:29
>I was wondering if there is a good reason why the sdclose function does not
>reset the SDEV_MEDIA_LOADED flag on the last close on the device. The unwanted
>(at least for me) side effect is that the disklabel will only be read on
>the first open.
This is a problem I have had as well. My problem was with some optical drives
e.g. Panasonic PD drive then mean the disklabel did not get reloaded
when I swapped disk. I just added a bit to sdclose() to clear this
flag on the last close.
I suspect that in my case the drive is meant to report a unit attention
command when the media is changed (this will cause a disklabel re-read)
but the pd drive does not do this which means that is it very easy to
trash PD discs unless sdclose is fixed.

Mark Brinicombe
Research Associate
Department of Physics			tel: 0171 873 2894
King's College London			fax: 0171 873 2716