PTYDRIVER is a VMS device driver which implements pseudo-terminal (PTY)
devices.  PHOTO is a program which uses the PTY device to exactly
log an interactive session.  This approach is superior to using mailboxes
since a PTY will execute ALL terminal QIO functions, such as those
performed by a text editor.  The driver is implemented as a port
driver to the VMS terminal class driver.  This allows most of the
difficult work to be done by TTDRIVER.

			     ** NOTICE **

Device drivers have the capability to crash your system.  There
are no known bugs in this driver which cause system crashes, and 
it is in regular use.  However, it has not been tested exhaustively and
the author assumes no responsibility for any crashes or other damages
caused by this software.

This driver will almost certainly not work under VMS V4.  It makes use
of various unsupported internal hooks in the terminal driver which are
expected to change.  We expect to rewrite this driver to work under
V4.

Below is a description of the files included in this submission:

BLDPHOTO.COM	- command procedure to build PHOTO program.
BLDPTYDRV.COM	- command procedure to build PTY driver
DESCRIP.MMS	- MMS description file to build PHOTO and PTY
PHOTO.EXE	- a prototype PHOTO program.  See comments for documentation.
PHOTO.MAR	- source for PHOTO program
PHOTOCMD.CLD	- command definition for PHOTO program
PHOTOMSG.MSG	- messages for PHOTO
PTYDRIVER.EXE	- PTY driver
PTYDRIVER.MAR	- PTY driver source   
PTYDRIVER.OPT	- linker options file for PTY driver
PTYDRIVER.RNO	- documentation for PTY driver
SMAC.MLB	- macro library for building PHOTO and XTALK
XTALK.MAR	- a simple program I used for testing PTY's.  It uses
		  single character QIO's between terminal and PTY