Notes on Slipper
----------------

Slipper and Cslipper are packet drivers for SLIP.  SLIPPER.EXE is the
packet driver for normal SLIP; CSLIPPER.EXE is the packet driver for CSLIP
(compressed SLIP, or SLIP with Van Jacobsen header compression).  Both
drivers can provide either SLIP (class 6) or Ethernet (class 1) packets to
applications - class 1 is better because more applications support it than
class 6.

You will need a dialer program and a packet driver terminator, since Slipper
and Cslipper don't come with either.  I use CHAT0.EXE from the Dospppd
distribution as a dialer.  Any other dialer or communications program can be
used if it is capable of dialing the phone, establishing a connection, and
exiting without dropping DTR.  The packet driver terminator is TERMIN.COM;
it is in the Dospppd distribution as well.

Slipper and Cslipper support BOOTP, but it may not work for you because your
ISP doesn't provide the necessary support at their end.  With my dynamic IP
account, BOOTP works.  To deal with dynamic IP in cases where the apps don't
support BOOTP, I'm using Ipread.

To dial and open my SLIP link, I created a batch file called SLIPOPEN.BAT,
which looks like this:

   @echo off
   chat0 -b 0x2e8 -i 5 -s 38400 -V -f chatopen.scr
   if errorlevel 1 goto failed
   cslipper port=2e8 irq=5 baud=38400 ether
   ipread "IP address is" > setip.bat
   call setip.bat
   echo my_ip=%MYIP% > ipaddr.cfg
   set ip=%MYIP%
   goto end

   :failed
   echo Dialup failed.
   goto end

   :end

My modem is at port 2E8, IRQ 5.  It is 14400 baud and uses data compression,
so I set the serial port speed to 38400 baud.

In this example, CHAT0.EXE dials the phone and logs me in using the script
CHATOPEN.SCR.  If it doesn't succeed, the batch file displays "Dialup
failed." and exits.  Otherwise, I load Cslipper using the same port, IRQ,
and baud rate as I used with CHAT0.EXE.  I specify "ether" since I want
Ethernet emulation, i.e., class 1 packets.  Note:  Slipper and Cslipper will
*always* load, regardless of whether you are dialed in or not, so you need
to check the return code from Chat.

Next, Ipread reads the IP address I was assigned off the screen - my ISP
displays "Your IP address is 206.139.113.25" (for example) when I log in. 
Ipread creates SETIP.BAT, which looks like this:

   @echo off
   set MYIP=206.139.113.25

I run that batch file to set the MYIP variable to my dynamic IP address. 
MYIP can be used by University of Minnesota applications.  Next, I configure
my WATTCP applications by creating a file, IPADDR.CFG, which is included in
my global WATTCP.CFG file.  IPADDR.CFG winds up looking like this:

   my_ip=206.139.113.25

Finally, I configure my Trumpet TCP applications by setting the IP variable
from MYIP.  I use BOOTP to configure my NCSA/CUTCP applications.

My dialing script for CHAT0.EXE, CHATOPEN.SCR, looks like this:

   TIMEOUT 10 "" \d\d\dATZ OK \d\d\dATDT9733710
   TIMEOUT 60
   ABORT BUSY ABORT "NO CARRIER" ABORT "NO DIALTONE" ABORT "NO ANSWER"
   CONNECT "\d\d\d\d\d"
   TIMEOUT 30
   name:--name: d\d\duserid
   ssword: \d\d\dpassword
   -gw> \d\d\dslip
   system. \d\d

(See CHAT.MAN in the Dospppd archive - the above is *not* for Agate, which
uses PPP unless you ask them for a SLIP account.)  My ISP (again, not Agate)
has adaptive SLIP so I could use either Slipper or Cslipper.  I use
Cslipper, which is supposed to provide better interactive response for
telnet.

To close the connection after I'm done with whatever Internet stuff I have
to do, I created another batch file called SLIPOUT.BAT, which looks like
this:

   termin 0x60
   chat0 -b 0x2e8 -i 5 -s 38400 -V -f chatout.scr

I run TERMIN.COM to unload the packet driver.  When Slipper and Cslipper are
unloaded, they don't hang up the phone line, so I run CHAT0.EXE again to do
that.  Again, the port base, IRQ, and speed are the same.  The hangup
script, CHATOUT.SCR, looks like this:

   TIMEOUT 10
   "" \d\d+++\d\d
   OK \dATH0
   OK \c

I imagine that script would work with any Hayes-compatible modem.  Of
course, if you prefer another dialer, you can use it to hang up your modem.
