Everhart Collection

The following are included
ASNVD_64.mar and VDD64.zip - latest VD: virtual disks for VMS on alpha
	which use contiguous files as disks. These programs have added
	one handly feature: the asnvd program will do a packack to
	ready any disk that is being used for a VD: unit that is 
	specified for /LBN treatment. Thus, mounting the underlying
	disk /foreign or /foreign/system is no longer needed.

IDEZR.zip and IDEZRPC.zip -
	These two zip files are the same except that one was made to
	be unpacked from VMS, the other being ok to unpack on a PC
	or the like. They implement zrdriver (and zsdriver which is
	the same as zrdriver but allows ucb$l_maxbcnt to be 32768
	instead of 8192 so you get less split transfers) and
	zridehost (and zsidehost which also allows larger nonsplit
	transfers).
	These utilities let ypu access SCSI devices that don't know 
	much SCSI and/or that have blocksize other than 512
	bytes. You connect a ZR unit 
e.g.
$ sysman io connect zra0:/noada/driver=sys$system:zrdriver

	and then set command zridehost and get the zridehost program
	running in a process and give it the ZR: unit name and the
	name of the device where the sort-of-scsi disk lives.
	This can be on a SCSI<->IDE converter (like the author's)
	or wherever you like. The command is something like

$ set command sys$sysetm:zridehost
$ zridehost zra0: gkb3:

	where in the example gkb3: would be the GK: unit (can be a
	DK: unit too) to which the physical disk is connected.

	This can be automated, presuming zrdriver, zridehost.cld,
	and zridehost.exe are in sys$system: somewhere, with a
	command something like

$ submit/param=(zra0:,gkb3:)zrddoany

	which will run things in batch (and incidentally load the
	ZR unit if need be). It presumes you have the privs to load
	drivers in the process.

	Build with @zridebld or @zsidebld and copy the .exe bits,
	the .cld files, and zrddoany.com if you like into sys$system.

	Zridehost uses io$_diagnose to read and write the disk, and
	requires only that the disk return its size and that read
	and write work. Thus it will work on most any SCSI disk.
	If the disk block size is not 512, the package will maintain
	an internal buffer and translate blocksize dynamically, so that
	the ZR: unit will appear as a normal 512-byte-block device
	regardless of what the actual underlying disk looks like.

	Works on VMS 7.3 or 7.3-1 alpha. Probably works on VAX also
	but build commands will need to be tweaked. Object files
	for the C programs are supplied so anyone can link the
	code.

Glenn Everhart
everhart@gce.com