Article View: vmsnet.internals
Article #420VD: as test device
From: raxco!galaxy.dnet!gleeve
Date: Mon, 09 Nov 1992 14:29
Date: Mon, 09 Nov 1992 14:29
31 lines
2349 bytes
2349 bytes
Re: Jon Pinkley's (kind) remarks about vddriver... The latest & greatest was in fdvdkit.zoo in the S92 tapes in [vax92a.gce92a.net92a]fdvdkit.zoo. Some later stuff and fqdriver.mar (a somewhat better fddriver.mar version) are in that directory also as separate files. Recent mods have mainly been in adding some new device geometries to the assign - VD image and setting it up so the device type gets set then instead of leaving dt$_FD1 in there for all disks. I use VD: drivers all the time for testing file structure hacks. It's also easy to change driver name to vdbdriver so I have two layers of them with separate drivers when I want to do weird hacking that involves munging driver tables. The lower and unmodified driver makes sure the rest of my system's disk space doesn't get scribbled on if something I do to a vdbdriver unit causes it to start clobbering its unit. Since the size and geometry of the VD: units can be easily controlled, I can be a little more sure those can't have any effect on my stuff. The recent hacks that cover setting the allocation class in the driver (thanks, Jon!) will be on the F92 tapes. They're real small but might be handy. Still, floppies are also handy where I want a removable and system-mountable device that I can test. I recently did a little hacking on passing ownership of mounted volumes around. A short hack that just changes the device owner UCB pointer does allow access, but dismount requires the mounted volume list to be messed with, and I haven't taken the time to find where that list header is to see about moving it around. The little hack lets me say something like $claimdevice devname:/pid:nnnnnnn to move the ownership of devname: to the process whose EPID is nnnnnnn, provided somebody else has it privately owned already. I'll post it if anyone is interested. Glenn Everhart@Raxco.com
Technical Details
Message-ID:
<9211091546.AA25232@relay2.UU.NET>Path:
arc1-ca.pugleaf.net!sparky!uunet!stanford.edu!agate!usenet.ins.cwru.edu!news.ysu.edu!malgudi.oar.net!caen!sol.ctr.columbia.edu!hamblin.math.byu.edu!arizona.edu!mvb.saic.com!macro32Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!stanford.edu!agate!usenet.ins.cwru.edu!news.ysu.edu!malgudi.oar.net!caen!sol.ctr.columbia.edu!hamblin.math.byu.edu!arizona.edu!mvb.saic.com!macro32 Newsgroups: vmsnet.internals Subject: VD: as test device Message-ID: <9211091546.AA25232@relay2.UU.NET> From: raxco!galaxy.dnet!gleeve@uunet.UU.NET Date: Mon, 9 Nov 92 09:29:00 -0500 Organization: Macro32<==>Vmsnet.Internals Gateway X-Gateway-Source-Info: Mailing List Lines: 31