Subject: Re: USB lpt and NOPRIME
To: Lennart Augustsson <>
From: Ignatios Souvatzis <>
List: tech-kern
Date: 02/09/2001 21:19:41
On Thu, Feb 08, 2001 at 11:41:02PM +0100, Lennart Augustsson wrote:
> "Johnny C. Lam" wrote:
> > In response to an inquiry about the USB printer code in CUPS, Michael
> > Sweet, the primary author of CUPS notes:
> >
> > The FreeBSD USB printer driver resets the USB printer on open,
> > unless you use the "unlptN" device.  This reset prevents some
> > printers from receiving the first bytes of the print job, which
> > then causes lots of spew... :(
> >
> > Is this properly a bug in the ulpt code, or a bug in the printer?  I
> > notice that NetBSD doesn't have /dev/unlpt[0-9]* devices.  Should we?
> > Or do we need to create some sort of quirks table for USB printers?
> I'm not sure where the bug is, but the USB code mimics the lpt driver
> which also resets on open (unless you use the NOPRIME bit).
> And sure enough, the same problem shows up on non-USB printers.
> My HP 870 doesn't print properly if I have the reset in the lpt driver.
> So perhaps this is a general lpt problem.  I suspect it is really a printer bug.

No, it is a driver bug.

You should not reset the printer when you KNOW it might still be printing
the old data, IMO.