bryanwi@microsoft.UUCP (Bryan Willman) (07/04/85)
Microsoft is working on the next release of DOS - which will be a full
multitasking system. This naturally requires some changes to the
print spooler package, as well as to the internal management of the
printer device driver and the ROM INT17 code.
In order to do this work in a way that won't break existing third
party printer systems, we need some information on how custom printer
drivers have actually written for Dos.
We're aware of three different ways that such a driver might be
implemented:
1. As a full blown dos installable device driver, that does not hook
int17, but communicates with applications through open, write, close,
etc.
2. As an installable device driver that hooks int17. (This amounts to
a terminate and stay resident that actually gets loaded at init time.)
3. As a terminate and stay resident program that hooks int17.
The question:
How are real world printer drivers actually done? We believe that
those printers which are not software compatible with the supported
IBM printers have packages which use technique #3 to support them. Is
anyone aware of any package that uses either of the other two
techniques, or a technique not listed? If so, please let us know
ASAP.
Thanks
Bryan Willman
Microsoft
/decvax \!microsoft!bryanwi
\uw-beaver/