
Guide to Watt-32 installation
==============================

This file guides you through obtaining, installing and using Watt-32.
Please read all of this guide before asking for help.

Watt-32 is a library for making networked tcp/ip programs in the
language of C and C++. Both 16-bit real-mode and 32-bit protected-mode
is supported. See README.TOO for table of supported environments.


1. DISTRIBUTION CONTENT
-----------------------

The latest release of Watt-32 is available at http://www.watt-32.net/.
The distribution consists of 3 separate .ZIP files where last part of name
indicates version and development release.  E.g. "watt32b-2.0-dev.2.zip"
indicates version 2.0 development release 2:

  watt32s-*.zip - Sources and tools required to build your own library.
                  This .zip-file isn't required if you don't need (or want)
                  to re-build the example programs. However, it's recommended
                  that you download this file also. See the `INSTALLATION'
                  section for usage.

  watt32b-*.zip - A collection of example programs showing how to use Watt-32.
                  All the original Waterloo example programs are contained
                  herein. Plus, I and others (Ken Yap in particular) have
                  ported some traditional BSD-socket programs to Watt-32.
                  These are:

                    archie   - Queries archie-servers for files.
                    bing     - ping tool with more statistics (djgpp only).
                    dig      - Domain Information Groper, DNS tool.
                    DOS-VNC  - Virtual Network Console; remote control (djgpp).
                    finger   - shows who is logged-in to a host.
                    fping    - fast, paralell ping client.
                    host     - Host/DNS tool.
                    ICMPpush - Generate custom ICMP messages.
                    IOctrl   - Server for accessing IO ports via Telnet.
                    MathOpd  - Small HTTP server.
                    netcat   - Read/write arbitrary data using TCP/UDP.
                    netio    - Network read/write performance (djgpp/Watcom).
                    netkala  - Kalahari networked game.
                    nslookup - Nameserver (DNS) query tool.
                    pchar    - Test network path characteristics.
                    popmail  - A simple POP3/SMTP mail client.
                    rdate    - Fetches date from time servers
                    rmtd     - Remote Magnetic Tape Daemon.
                    syslogd  - A syslog daemon program.
                    syslogd2 - Another syslog daemon program.
                    suck     - NNTP articles retriever/poster.
                    talk     - Talk client/server, chat via Internet.
                    ttcp     - TCP/UDP performance tool.
                    tftpd    - Trivial File Transfer daemon.
                    vrfy     - Verifies Email addresses.
                    wget     - http/ftp file retriever.

                  See their respective directories (under the .\bin\ direc-
                  tory) for detail.  The example programs are mostly client-
                  side implementations of various standard Internet protocols.
                  But some daemons (servers) are provided too.

                  NOTE: Some of these programs have been very little tested
                        with Watt-32. Don't yell if they don't work. Contribute
                        a fix instead. You'll need to use the command:
                        `make -f makefile.dj depend' to remake dependencies.

  watt32d-*.zip   A collection of Unix man-pages (actually cat-files), RFCs
                  and html-files.


2. QUICK INSTALLATION
---------------------

These steps assumed you have installed "watt32*.zip" into directory
"c:\net\watt". It it *not* advisable to install into a directory containing
spaces. E.g. "c:\Program Files\watt\" will probably *not* work.

1. Unzip "watt32*.zip" and do "set WATT_ROOT=c:\net\watt"

2. In .\src do "configur.bat <your-compiler>". Run "configur.bat -?" for
   possible targets.

3. Run your make. E.g. "make -f djgpp.mak" for a djgpp version.

4. Change to .\bin and try building some sample applications with the
   library you just built. Then do a "set WATTCP.CFG=c:\net\watt\bin"
   before running any samples. Try "tcpinfo.exe" to see if everything is
   setup correctly. I.e. the packet-driver or WinPcap is installed correctly.
   WinPcap is available at <https://www.winpcap.org/install/>

5. If something doesn't work, refer the INSTALLATION DETAILS below or
   email the Watt-32 mailing-list at <watt-32@yahoogroups.com>. Go here
   to join: <http://groups.yahoo.com/group/watt-32/join>



3. INSTALLATION DETAILS
-----------------------

Follow these steps closely:

1. Create a new top-level directory for extraction of Watt-32 zip files.
   E.g. `c:\net\watt'


2. All three .ZIP files `watt32[bsd]*.zip' contain subdirectories, so
   remember to use the `-d' option when extracting using `pkunzip' or
   `unzip'.

   Unzip all Watt-32 zip files into this new directory.
   There's are no long-file names (LFN), so pkunzip or unzip for
   DOS is safe to use. E.g. use this command to extract:
     `pkunzip -d watt*.zip c:\net\watt'.

   All three .ZIP files have some files in common (MANUAL.TXT, README.*,
   CHANGES, INSTALL and BIN\*.cfg).  If the .ZIP files are of the same
   version, the common files should be the same.  Then these files can
   safely be overwritten.  With pkunzip, use option `-o' or press `o'
   when prompted.  Otherwise make sure the oldest ZIP-file is extracted
   first.


3. Create an environment variable `WATT_ROOT' pointing to this directory.
   E.g. `WATT_ROOT=c:\net\watt'.

   NOTE: no spaces on either side of `=' and no trailing `\'. This variable
   is used by the various makefiles to access the sub-directories `.\inc'
   and `.\lib'.

   NOTE: DO NOT RENAME ANY OF THE SUB-DIRECTORIES.

   If you are using djgpp and want to compile under Win95/98/XP, you should
   create the environment variable `LFN=n' (or edit `djgpp.env').


4. If your're NOT building for Pharlap DOS-extender (*), proceed to step 5.

   Define an environment variable `PHARLAP' to specify root directory for
   Pharlap's files.

   Pharlap targets (*) requires the use of an exception-handling library
   of mine. This is available from:
     http://www.watt-32.net/misc/exc_dx07.zip

   Install this library before proceeding. The assumed location for the
   `exc.h' header file is in a sub-directory `mw' somewhere specified by
   your `INCLUDE' or `IPATH' environment variable. The Watcom compiler use
   the `DOS_INCLUDE' variable.
   E.g. say:
      SET DOS_INCLUDE=C:\WATCOM\H;C:\EXCEPT

   in you AUTOEXEC.BAT. Otherwise, see install guide for the exception
   library.

    (*) Currently Metaware's HighC and Watcom's wcc386 are supported.
        Default target for wcc386 is DOS4GW (or similar; DOS32A, PmodeW
        or WDOSX).  Edit `.\src\target.h' to specify PHARLAP target. At
        around line 90, change to:
           "#define DOSX PHARLAP"


5. The configure process (in step 7 below) uses some programs in the
   `$(WATT_ROOT)\util\' directory.  Some of these programs (mk*.exe)
   requires the use of a DPMI-server (because they are compiled with djgpp).
   If you are running Win9x/ME/NT/XP you should already have a DPMI-server
   present.  Otherwise you would need `$(WATT_ROOT)\bin\cwsdpmi.exe'.

   If you don't have a 80387 math processor, you would also need an
   emulator contained in `$(WATT_ROOT)\bin\emu387.dxe'.

   Copy the following files:
     `$(WATT_ROOT)\bin\cwsdpmi.exe' and `$(WATT_ROOT)\bin\emu387.dxe'

   to a directory on your PATH.  The best thing is to edit your `AUTOEXEC.BAT'
   and include `$(WATT_ROOT)\bin' in your `PATH' statement.

   The programs `*_err.exe' and `win32/*_err.exe' are tools to produce a list
   of errno's and a `sys_errlist[]' (or `_sys_errlist[]') which also includes
   network related errno's.  These lists are included in `$(WATT_ROOT)\src\neterr.c'
   and `$(WATT_ROOT)\inc\sys\werrno.h'.

   You may have to rebuild one of these tools if you upgrade your compiler
   and/or the vendor changes the `errno' numbering.  Normally, simply
   proceed to next step.

   The rationale behind `errnos.c', is to extend the vendor's normal `errno'
   range without redefining existing errno's or producing holes in the range.
   The lists produced by `*_err.exe' + `win32/*_err.exe' and the functions in
   `neterr.c' (`perror' and `strerror'), will hopefully replace the existing
   functions in your C-library without harming it's function.

   `neterr.c' shall simply extend `sys_errlist[]' (or `_sys_errlist[]')
   so it will give meaningful texts for network related errors.

   BTW. some vendors have `__sys_errlist[]', which will NOT be updated
        by the `neterr.c' module.

   To recompile the `mk*.exe' tools you need:
     Compiler GCC 2.7.1 + djgpp 2.01 or later and
     S-Lang library avalable at <http://space.mit.edu/~davis/slang.html>
     Change `.\util\makefile' to suite your location of S-Lang.

   To recompile the `*_err.exe' tools you need:
     Borland/Turbo C and Borland `make'  - to produce `bcc_err.exe'.
     Watcom C (16-bit) and `wmake'       - to produce `wc_err.exe'.
     GNU C + djgpp 2.x and GNU `make'    - to produce `dj_err.exe'.
     GNU C + MinGW and GNU `make'        - to produce `mw_err.exe'.
     Digitial Mars C  and Borland `make' - to produce `dm_err.exe'.
     Metaware HighC + Pharlap SDK        - to produce `hc_err.exe'
     Microsoft Visual C and `nmake'      - to produce `vc_err.exe'
     PellesC and `pomake'                - to produce `po_err.exe'
     Clang and any make program          - to produce `clang_err.exe'

     E.g. for Borland issue this command:
        C:\NET\WATT\UTIL\>make -f errnos.mak bcc_err.exe

   *_err.exe have three command-line options:
     -e :  produces a list of all errno's
     -s :  produces the `sys_errlist[]' array
     -t :  test; prints a list of "normal" errno's defined by
           vendors compiler. Mainly for verifying -e option.

   NOTE: only one (the first) option is handled.

   All printout of data is on `stdout'. Data must be redirected to
   correct file. E.g:

     "bcc_err.exe -e > ..\inc\sys\borland.err"
       produces an include file for `.\inc\sys\werrno.h' and Borland
       targets.

     "dj_err.exe -s > ..\src\build\djgpp\syserr.c"
       produces a replacement `sys_errlist[]' for inclusion in
       `.\src\neterr.c'.

   NOTE: If you have djgpp 2.04 installed and the `dj_err.exe' was compiled
         with 2.03 (or older), you *MUST* recompile `dj_err.exe' to fit the
         new errnos added in 2.04 (ELOOP, EILSEQ etc.). Simply do a
         "make -f errnos.mak dj_err.exe" in the .\util\ directory.


6. If you've played with Watt-32 for a while and would like to change some
   build settings or features, study this step. Otherwise, accept things
   as they are and proceed to next step.

   The `makefile.all' is a master makefile from which all makefiles will
   be generated. The compiler switches and options are chosen to best suite
   the majority of user. I.e. Borland users with only a 386-PC would probably
   be upset if `makefile.all' would optimise for a Pentium based PC.  Study
   the sections (inside `ifdef BORLAND', etc.) carefully before making any
   changes. Refer to your compiler documentation for details.

   djgpp users may benefit by specifying `-fomit-frame-pointer' in `CFLAGS'.
   This isn't done by default to ease debugging and traceback when crashes
   occur.  Only specify this flag when confident your application as a whole
   (with all libraries) is stable and bug-free.  Watcom users could likewise
   remove `f' from the list of `-o'ptimise flags.

   The list of features compiled into Watt-32 is determined by settings in
   `.\src\config.h'. For small and large memory-models the list of features
   is severely limited.  Small model doesn't include the TCP protocol (only
   UDP and ICMP).  You may change this if you like, but note that the data-
   segment (DGROUP) will overflow easily.  The size of code and data could
   be reduced significantly by only using the define `USE_FRAGMENTS'.  This
   should AFAIK build a minimum compliant TCP/IP stack.  Refer RFC-1122 and
   RFC-1123 for requirements.

   The module '.\src\version.c' tries to detect what CPU the compilation was
   optimised for and the function `wattcpVersion()' returns this and other
   info at run-time.  Run the `.\bin\tcpinfo.exe' program to check.  You
   should see something like this:

     [..]

     Version info  : Watt-32 (2.1.0), GNU C 2.95 (486), djgpp 2.x, Jan 12 2000
     Capabilities  : /debug/bsdsock/bootp/dhcp/lang/frag/stat/bsdfatal/
                     bsdfortify/fsext/loopback/tftp

     Which simply states the Watt-32 version is v2.1.0 compiled with
     GNU C 2.95, optimised for 80486 (-mcpu=486 switch) and library built
     date.  "Capabilities :" lists the features defined in `.\src\config.h'.


7. Run the `configur.bat' to generate the makefiles, sub-directories, list of
   errno's and `sys_errlist[]' and dependency file for the library you want.
   `configur.bat' takes at least one of these parameters:

     borlandc -> Produces these makefiles for making Borland-C targets:
                  `bcc_s.mak'  - For DOS small model.
                  `bcc_l.mak'  - For DOS large model.
                  `bcc_f.mak'  - For DOS flat model.
                  `bcc_w.mak'  - For Win32.
                + `build\borland\watt32.dep'.

     watcom   -> similar for Watcom.
     digmars  -> similar for Digital Mars.
     highc    -> `highc.mak' and `build\highc\watt32.dep'.
     clang    -> `clang_32.mak', `clang_64.mak' and `build\clang\watt32.dep'.
     djgpp    -> `djgpp.mak'       + `build\djgpp\watt32.dep'.
     ladsoft  -> `ladsoft.mak'     + `build\ladsoft\watt32.wat'.
     mingw32  -> `mingw32.mak'     + `build\MinGW32\watt32.dep'.
     mingw64  -> `mingw64_32.mak', `mingw64_64.mak' and `build\MinGW64\watt32.dep'.
     cygwin   -> `cygwin_32.mak', `cygwin_64.mak' and `build\Cygwin\watt32.dep'.
     visualc  -> `visualc-*.mak' and `build\visualc\watt32.dep'.
     pellesc  -> `pellesc.mak'     + `build\pellesc\watt32.dep'.
     lcc      -> `lcc.mak'         + `build\lcc\watt32.dep'.
     all      -> All of the above.
     clean    -> deletes all generated `*.mak', `watt32.dep',
                 `syserr.c' and `.\inc\sys\*.err' files.

   E.g. To make small and large libraries for Borland,
        use the command `configur borlandc' followed by `make -f bcc_s.mak'
        and `make -f bcc_l.mak'.

   You can e.g. say:

     C:\NET\WATT\SRC\configur borland djgpp

   to prepare building all Borland and djgpp targets. This command would
   produce the following files for both Borland and djgpp:

     .\src\bcc_s.mak                ->  Borland Makefiles (small, large, flat and Win32)
     .\src\bcc_l.mak
     .\src\bcc_f.mak
     .\src\bcc_w.mak

     .\src\djgpp.mak                -> GNU Makefile for djgpp target.

     .\src\build\borland\watt32.dep -> Dependency file for Borland targets.
     .\src\build\djgpp\watt32.dep   -> Ditto for djgpp.

     .\src\build\borland\syserr.c   -> Included in .\src\neterr.c (Borland)
     .\src\build\djgpp\syserr.c     -> Included in .\src\neterr.c (djgpp)

     .\inc\sys\borland.err    -> Included in .\inc\sys\werrno.h (Borland)
     .\inc\sys\djgpp.err      -> Included in .\inc\sys\werrno.h (djgpp)


   NOTE: All makefiles (except `djgpp.mak') generates additional files needed
         to compile and create resulting libraries.  This is because DOS's
         command-line is limited to only 128 characters.  djgpp has a limit of
         16kB, hence no response files are needed.

   NOTE: "configur.bat visualc" generates makefiles for both release and debug
         modes (cl option `-MD' and `-MDd'). Issue this command for a release
         version:
           C:\NET\WATT\SRC\> nmake -f visualc-release_32.mak


8. Building the source distribution WATT32S*.ZIP requires these tools:

   For djgpp:   DJGPP 2.01 or later (djgpp 2.00 not tested) from:
                  ftp://ftp.delorie.com/pub/djgpp/current/v2/
                GCC 4.7 or later, (including `cpp' and `ar')
                GNU Make 4 or later.

   For Borland: Only Borland C 4.5 has been tested.
                Borland's TASM (3.0 or later).
                Borland's MAKE tool, linker and librarian.
                NOTE: BCC32 users who doesn't have `tasm32.exe' can
                      safely use `-E<bcc32-bin-path>\tasm.exe' in the
                      BCC32 config-file (`<bcc32-bin-path>\bcc32.cfg').

   For Watcom:  Only Watcom C v11.0A and OpenWatcom 1.x has been tested.
                Watcom's assembler WASM, make tool WMAKE, linker WLINK
                and librarian WLIB are required.
                E.g. `wmake -f watcom_s.mak clean' will erase all temporary
                files generated by Watcom/small.

   For Microsoft (DOS): This target (i.e. Quick-C) has been dropped.

   For Visual C (Win32): Currently ML (Microsoft's Macro Assembler) is required
                for all .asm files. You can get it from the Windows SDK. It is
                available here:
                  http://www.microsoft.com/en-us/download/details.aspx?id=12654

   For HighC:   Metaware HighC 3.1 and 3.61 has been tested.
                Pharlap DOS-extender 4.0 or later (including 386link linker
                and 386lib librarian) required.
                Borland's TASM (3.0 or later).
                Borland compatible MAKE tool (MWMAKE stinks!).

                NOTE: the `MAKE.EXE' from recent (v4.0 onwards) Borland
                      versions is a protected mode program which is in-
                      compatible with hc386.exe (a Pharlap DOSX-program).
                      Hence use the real-mode `MAKER.EXE' instead.

   For DMC:     Digital Mars Compiler prior to v8.33 has not been tested.
                Borland's TASM (3.0 or later).
                Borland compatible MAKE tool (SMAKE stinks!).

                To compile for both MS Quick-C and Digital Mars is a bit
                tricky. Because they both have lib.exe and link.exe programs
                in their bin directories, and they both use `$INCLUDE' to
                search for header files. We therefore use an environment
                variable `DIGMARS'. This should point to the Digital Mars
                base directory. E.g. define "set digmars=c:\dmc" in your
                environment.

   For all: To make library after changing `.\src\language.l',
            GNU Flex 2.5.4 (or newer) is required. Download from:
              http://gnuwin32.sourceforge.net/packages/flex.htm

   Hint: If you have a RAM-disk of at least 5 Mbyte, building djgpp target
         may be speeded up by defining a `TMPDIR' directory on a RAM-disk;
         Assuming RAM-disk is on `d:', change `$(DJDIR)/djgpp.env' to include
         `TMPDIR=d:/'.  Speed up building for Metaware by defining `TMPPREFIX'.
         E.g. `SET TMPPREFIX=d:\'.


9.  Make your library with the generated makefile (see above). All libraries
    produced are placed in the `.\lib\' directory. The libraries are named:

     For DOS:
     ----------------------------------------------------------
     .\lib\wattcpBS.lib  - Borland      Small (16-bit) version
     .\lib\wattcpBL.lib  - Borland      Large (16-bit) version
     .\lib\wattcpBF.lib  - Borland      Flat  (32-bit) version
     .\lib\wattcpTS.lib  - Turbo-C      Small (16-bit) version
     .\lib\wattcpTL.lib  - Turbo-C      Large (16-bit) version
     .\lib\wattcpHF.lib  - HighC        Flat  (32-bit) version
     .\lib\wattcpWS.lib  - Watcom       Small (16-bit) version
     .\lib\wattcpW3.lib  - Watcom       Small (32-bit) version
     .\lib\wattcpWL.lib  - Watcom       Large (16-bit) version
     .\lib\wattcpWF.lib  - Watcom       Flat  (32-bit) version
     .\lib\wattcpDS.lib  - Digital Mars Small (16-bit) version
     .\lib\wattcpDL.lib  - Digital Mars Large (16-bit) version
     .\lib\wattcpDF.lib  - Digital Mars Small (32-bit) version (!)
     .\lib\libwatt.a     - djgpp        Flat  (32-bit) version

     For Win32 targets (32-bit):
     ----------------------------------------------------------------------------
     .\lib\x86\wattcpvc.lib         - Visual C,  static lib (release)
     .\lib\x86\wattcpvc_d.lib       - Visual C,  static lib (debug)
     .\lib\x86\wattcpvc_imp.lib     - Visual C,  import lib for .\bin\watt-32.dll  (release)
     .\lib\x86\wattcpvc_imp_d.lib   - Visual C,  import lib for .\bin\watt-32d.dll (debug)

     .\lib\libwatt32.a              - MinGW, static lib
     .\lib\libwatt32.dll.a          - MinGW, import lib for .\bin\watt-32.dll
     .\lib\x86\libwatt32.a          - MinGW-w64, static lib
     .\lib\x86\libwatt32.dll.a      - MinGW-w64, import lib for .\bin\watt-32.dll

     .\lib\wattcpww.lib             - Watcom C,  static lib
     .\lib\wattcpww_imp.lib         - Watcom C,  import lib for .\bin\watt-32.dll

     .\lib\wattcppo_imp.lib         - PellesC,   import lib for .\bin\watt-32.dll
     .\lib\wattcppo.lib             - PellesC,   static lib

     .\lib\x86\wattcp_clang_imp.lib - Clang-cl,  import lib for .\bin\watt-32.dll
     .\lib\x86\wattcp_clang.lib     - Clang-cl,  static lib

     For Win64 targets (64-bit):
     ----------------------------------------------------------------------------
     .\lib\x64\wattcpvc.lib           - Visual C,  static lib (release)
     .\lib\x64\wattcpvc_d.lib         - Visual C,  static lib (debug)
     .\lib\x64\wattcpvc_imp.lib       - Visual C,  import lib for .\bin\watt-32_64.dll  (release)
     .\lib\x64\wattcpvc_imp_d.lib     - Visual C,  import lib for .\bin\watt-32d_64.dll (debug)

     .\lib\x64\libwatt32.a            - MinGW-w64, static lib
     .\lib\x64\libwatt32.dll.a        - MinGW-w64, import lib for .\bin\watt-32_64.dll

     .\lib\x64\wattcp_clang.lib       - Clang-cl,  static lib (release)
     .\lib\x64\wattcp_clang_d.lib     - Clang-cl,  static lib (debug)
     .\lib\x64\wattcp_clang_imp.lib   - Clang-cl,  import lib for .\bin\watt-32_64.dll  (release)
     .\lib\x64\wattcp_clang_imp_d.lib - Clang-cl,  import lib for .\bin\watt-32_64_d.dll  (debug)


     The above 'MinGW' is the old-school version from 'http://mingw.org'. I.e. pretty much a dead project.
     (other compilers are not currently supported for 64-bits.)


   NOTE: A handy tip for djgpp users; make a hard link between
         `libwatt.a' and `/djgpp/lib/libsocket.a' by this command:

         ln -f $WATT_ROOT/lib/libwatt.a $DJDIR/lib/libsocket.a

         (soft links doesn't work for anything except .exe-files.)

         djgpp users should also define environment variables
         `C_INCLUDE_PATH' and `LIBRARY_PATH' to point to the include
         directory and library directory respectively.  E.g. put this
         in your AUTOEXEC.BAT:

           set C_INCLUDE_PATH=c:/net/watt/inc
           set LIBRARY_PATH=c:/net/watt/lib

         `C_INCLUDE_PATH' and `LIBRARY_PATH' are used in `djgpp.env' and
         read by gcc when compiling and linking. Compiling the Watt-32
         library and samples does not require these variables, but they
         make it easier to build other applications. I.e. compiling
         and linking could be as easy as `gcc ping.c -o ping.exe -lwatt'.

         (!) Yes, the 32-bit Digital Mars version is actually SMALL model
             (not FLAT). I choose the letter 'F' to be consistent with
             other 32-bit versions.

   NOTE: Building for PellesC [*] under Windows assumes you have created an
         environment variable %PELLESC% to point to the root directory
         of PellesC files.
         [*] http://www.smorgasbordet.com/pellesc/


10. Create the following environment variables:

    * `WATTCP.CFG' (or `WATTCP_CFG' if you're using bash) pointing to
      the directory where configuration-file `WATTCP.CFG' is located.

    * `ETC' pointing to the directory where the files `hosts', `services',
      `protocol' and `networks' are located.

      E.g. SET WATTCP.CFG=c:\net\watt\bin
           SET ETC=c:\net\watt\bin

   NOTE: no trailing `\' at end of value (allthough wouldn't hurt).
         Change the paths or environment variables in `WATTCP.CFG' to
         match your setup.

   NOTE: The `WATT_ROOT' variable created in step 3 above is NOT required to
         run any Watt-32 programs. It's only used during the build process.


11. Waterloo TCP/IP currently uses only a single real-mode packet-driver
   (PKTDRVR) to access the link-layer (Ethernet, PPP etc). For information
   on how to obtain or install a packet-driver, look elsewhere. It is
   assumed you are familiar with it's use.

   Watt-32 have no concept of `interfaces' to route packets to.  Only one
   interface exists at a given time. (But it handles routing to proper
   gateway off course).

   Default behaviour is that the first packet-driver in the range 0x60 -
   0x80 will be used.  If you have more than one packet-driver installed,
   this may cause troubles;  E.g. If you have an EtherNet PKTDRVR at
   interrupt 0x60 and you want to connect via e.g. Dos-PPP at interrupt
   0x61, Watt-32 will choose to use the EtherNet driver.

   To solve this situation, set the WATTCP.CFG variable `PKT.VECTOR=0xNN'.
   Replace `NN' for the API interrupt of the driver you want to use.  This
   way, no PKTDRVR searching is done; only the driver at interrupt `0xNN'
   will be used.

   NOTE: To solve the above situation without using the `PKT.VECTOR' variable,
         make sure your EtherNet driver is installed on a interrupts higher
         than the one Dos-PPP will use.  That way the lowest interrupt number
         will always be the correct one.  I.e. DOS-PPP will grab 0x60 when
         online.  When offline, only the EtherNet driver at 0x61 will exist.


WEAKNESSES (-) and BUGS (!)
---------------------------

There are still bugs. Especially with the BSD-socket API:

! The IP-reassembly doesn't properly handle IP-fragments in random order.
  Especially when the first fragment sent is the last fragment received.
  But sequential order is okay. Linux has the habit of always sending the
  IP-fragment with the highest offset first. This speeds up memory alloc-
  ation at the receiver side (because size is known), but may cause problems
  for Watt-32 hosts.

- You cannot send packets larger than link-layer MTU because IP-fragmentation
  on output is not yet supported. Will most likely only be supported for
  BSD-sockets.

! The Initial Sequence Number (ISN) is selected from system-timer.
  With local ports being reused more quickly than our peer accepts,
  the connection will be reset. We should wait 60s (2*MSL) before reusing
  a local port.

! Running with PPPD (ppp link driver) seems to indicate OOB ("Out Of Band")
  is received in some tcp segments. I don't know if this is a bug in the
  protocol debugger (pcdbug.c) or in PPPD. However, Watt-32 doesn't support
  OOB or urgent data.


