Dear SCO Customer,

Support Level Supplement (SLS) ptf7646b, the UnixWare 7 lp Driver 
Supplement, addresses all of the problems listed below.

SLS ptf7646a addressed this issue:

1. The lp driver stops responding if a process that is writing 
   to it is killed.

SLS ptf7646b additionally addresses this issue:

2. Printing via the parallel port is extremely slow. (This is especially
   known to occur on some Compaq systems.)

   There is a timing issue between the response from some printers 
   on the parallel port and the retry wait loop code. This causes 
   the printer to go into a wait after each character is printed.

   This has been resolved by creating a configurable wait tunable,
   lp_parallel_wait, which is present in a new lp space.c. This allows 
   the tuning of a wait time before going into the retry wait loop.
   
   The value of lp_parallel_wait can range from 80 to 1000000 (one second). 
   It will be necessary to experiment with this value to restore normal 
   printing speed.


Contents
--------

        /etc/conf/pack.d/lp/Driver_atup.o
        /etc/conf/pack.d/lp/Driver_mp.o
        /etc/conf/pack.d/lp/space.c


Software Notes and Recommendations
----------------------------------

SLS ptf7646b should only be installed on:

        UnixWare 7 Release 7.0.1, 7.1.0, 7.1.1

NOTE:  This supplement has been superseded by
the UnixWare 7.1.1 Maintenance Pack for UnixWare 7.1.1 platforms
only.  The UnixWare 7.1.1 Maintenance Pack is available from:

ftp://ftp.caldera.com/pub/unixware7/uw711pk



Installation Instructions
-------------------------

1. Download the ptf7646b.Z file to the /tmp directory on your machine.

2. As root, uncompress the file and add the SLS package to your system
   using these commands:

        $ su
        Password: <type your root password>
        # uncompress /tmp/ptf7646b.Z
        # pkgadd -d /tmp/ptf7646b
        # rm /tmp/ptf7646b

Alternatively, this SLS package may be installed in quiet mode, 
that is, without displaying the release notes and asking for 
installation confirmation.  To do this, use these commands:

        $ su
        Password: <type your root password>
        # uncompress /tmp/ptf7646b.Z
        # pkgadd -qd /tmp/ptf7646b all
        # rm /tmp/ptf7646b

3. Reboot the system after installing this SLS package.

The release notes displayed prior to installation can be found in:

        /var/sadm/pkg/ptf7646/install/ptf7646.txt


Removal Instructions
--------------------

1. As root, remove the SLS package using these commands:

        $ su
        Password: <type your root password>
        # pkgrm ptf7646

2. Reboot the system after removing this SLS package.

If you have questions regarding this SLS, or the product on which 
it is installed, please contact your software supplier.