Re: Direct access to parport

Peter Svensson (
Wed, 5 Mar 2003 07:49:23 +0100 (CET)

On Tue, 4 Mar 2003, Eric Lammerts wrote:

> On Tue, 4 Mar 2003, Uwe Reimann wrote:
> > I'd like to connect some self made hardware to the parallel port and
> > read the values of the dataline using linux. Can this be done in
> > userspace or do I have to write kernel code to do so? I'm currently
> > thinking of writing a device like lp, which in turn uses the parport
> > device. Does this sound like a good idea?
> >From userspace it's quite simple:

[ioperm-based suggestion removed]

A better idea may be to use ppdev - the portable and safe way to access a
paralell port directly. This driver is in the stock kernels. This prevents
races between the kernel and userland over control for the paralell port.


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