.\"	$NetBSD: pud.4,v 1.4 2011/02/01 18:08:38 pooka Exp $
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.\" Copyright (c) 2007 Antti Kantee.
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.Dd November 21, 2007
.Dt PUD 4
.Os
.Sh NAME
.Nm pud
.Nd Pass-to-Userspace Device
.Sh SYNOPSIS
.Cd "pseudo-device pud"
.Cd "pseudo-device putter"
.Sh DESCRIPTION
The
.Nm
driver enables the implementation of block and character device drivers
as userspace daemons.
The daemons register the device major number they wish to handle.
Registering a character device is mandatory, supporting the block
device interface for same major device is optional.
The major number must be available, i.e. another driver must not
be registered to handle the operation.
After successful registration the userspace daemon is supposed to
handle the driver methods the kernel passes down to it.
.Sh SEE ALSO
.Xr puffs 4 ,
.Xr putter 9
.Sh BUGS
This document is in a hit-in-the-head style obviously not even
near complete.
.Pp
The subsystem lacks a puffs-style library that servers can be
written against.