Patch-ID# 100368-01
Keywords: HUPCL, dial in, serial, DTR, modems, zs_async.c
Synopsis: SunOS 4.1.1:  SunOS doesn't handle tilde HUPCL correctly
Date: 30-Aug-91
 
SunOS release: 4.1.1
 
Topic: 
 
BugId's fixed with this patch: 1068641, 1056787

Architectures for which this patch is available: sun4, sun4c

Patches which may conflict with this patch:  100188 100187 100315 100358 

Obsoleted by: 

Problem Description:
	SunOS doesn't handle ~HUPCL correctly. Typically this is seen
	when one dials in to a Sun zs port, and starts a process which
	is supposed to remain attached to the modem after you log off
	(E.g. a dialback program). When you log off, SunOS 4.1.1 will
	drop DTR. This causes the remaining process to detach from
	the modem. See escalation #790.

	Note well that this has been evaluated by Engineering, and that
	a fix for it *won't* be available in 4.1.2. It is their recommendation
	that this patch be applied to 4.1.2 for those customers who need
	it. 


INSTALL:

cp /sys/{sun4, sun4c}/OBJ/zs_async.o /sys/{sun4, sun4c}/OBJ/zs_async.o.FCS
cp {sun4, sun4c}/zs_async.o /sys/{sun4, sun4c}/OBJ/zs_async.o

Regen the kernel and reboot with the new kernel.

     Please Refer to the System and Networking Administration Manual
             section on building and installing a custom kernel.