kern/47324: ulpt(4) and ulpn(4) loose data

[marc%msys.ch@localhost]

>Number:         47324
>Category:       kern
>Synopsis:       ulpt(4) and ulpn(4) loose data
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Dec 14 08:30:00 +0000 2012
>Originator:     Marc Balmer
>Release:        5.1.0 and 5.1.2
>Organization:
micro systems
>Environment:
NetBSD xxx 5.1.2_PATCH NetBSD 5.1.2_PATCH (GENERIC) #18: Thu Dec  6 17:06:34 
CET 2012  root@netbsd-5-1:/usr/obj/sys/arch/i386/compile/GENERIC i386

>Description:
When open()in /dev/ulpt0 or /dev/ulpn0 and then immediately write()ing data, 
the first byte gets lost in most cases.  Tested on different hardware and with 
different (receipt) printers.
>How-To-Repeat:
Write a small program that open()s /dev/ulpt0 and send e.g. an escape sequence 
to open a cash drawer.  The cash drawer will not open in most cases, because 
the the initial byte gets lost.
>Fix: