[net.micro.pc] need info about DOS drivers

kbb@faron.UUCP (Kenneth B. Bass) (02/06/85)

	I am trying to write a DOS driver. But the information
I have about them (mainly DOS technical reference manual) doesn't
go into great detail about how DOS accesses them. Mainly:

	- when does DOS use the ioctl commands (assuming that the
	  ioctl bit is set in the attribute word in the header),
	  as opposed to the other read/write commands? Does DOS
	  only use the ioctl commands when a program reads or
	  writes to that device, or can the program choose - and
	  if the program can choose, how does it? (ie., how can a 
	  driver have both a data and control channel and how does
	  a calling program choose whcih channel?)

	- how do you access the driver from a high level language
	  (like 'C', or pascal)?

	- what happens if the driver returns an error? Does DOS
	  freak out, or does it return the error code to the calling
	  program, or does it just ignore it?

If anyone knows of any good books/manuals/articles about this,
please send me info about them (name, author, where to buy, etc.).

	Thanks,

				ken bass
				linus!faron!kbb