VDDRV FOR IAS
This set of programs (vddrv, vdkdrv, vdprv) is a virtual disk
driver for IAS or RSX11D which was originally written about
1977. It provides virtual data disks only (must NOT run tasks
from them), but allows encryption and MUCH access checking
of access to the virtual disks, providing secure subsystems
if this is desired. Replacing the ..BLXI or ..BLXO calls
with functions that can run with no task context will allow
this driver to load tasks too. Note vdkdrv is a version that
does not ask passwords or provide encryption, just raw virtual
disks.
Glenn Everhart

ASDEV and its companion program, ASSIGN, give IAS a virtual device
that is terminal-like. However, input and/or output may be assigned
to files, and optionally output may also go to a terminal as well
as a file; the ASSIGN task controls this. It gives IAS users a
means to arrange for programs that try to do I/O to terminals to
have that I/O captured to a file. It was devised for use with a
virtual RT11 V2C which did QIO$ directly to LP:, where the desired
effect was to spool the output. However its applicability was much
wider. All filename parsing is in the driver, allowing a VERY simple
program interface to do file I/O (just issue a special QIO with the
filename string; the driver does the rest).