
Basic Installation on Unix
==================

   These are generic installation instructions.

   The `configure' shell script attempts to guess correct values for
various system-dependent variables used during compilation.  It uses
those values to create a `Makefile' in each directory of the package.
It may also create one or more `.h' files containing system-dependent
definitions.  Finally, it creates a shell script `config.status' that
you can run in the future to recreate the current configuration, a file
`config.cache' that saves the results of its tests to speed up
reconfiguring, and a file `config.log' containing compiler output
(useful mainly for debugging `configure').

   If you need to do unusual things to compile the package, please try
to figure out how `configure' could check whether to do them, and mail
diffs or instructions to the address given in the `README' so they can
be considered for the next release.  If at some point `config.cache'
contains results you don't want to keep, you may remove or edit it.

   The file `configure.in' is used to create `configure' by a program
called `autoconf'.  You only need `configure.in' if you want to change
it or regenerate `configure' using a newer version of `autoconf'.

The simplest way to compile this package is:

  1. `cd' to the directory containing the package's source code and type
     `./configure' to configure the package for your system.  If you're
     using `csh' on an old version of System V, you might need to type
     `sh ./configure' instead to prevent `csh' from trying to execute
     `configure' itself.

     Running `configure' takes awhile.  While running, it prints some
     messages telling which features it is checking for.

  2. Type `make' to compile the package.

  3. Optionally, type `make check' to run any self-tests that come with
     the package.

  4. Type `make install' to install the programs and any data files and
     documentation.

  5. You can remove the program binaries and object files from the
     source code directory by typing `make clean'.  To also remove the
     files that `configure' created (so you can compile the package for
     a different kind of computer), type `make distclean'.  There is
     also a `make maintainer-clean' target, but that is intended mainly
     for the package's developers.  If you use it, you may have to get
     all sorts of other programs in order to regenerate files that came
     with the distribution.


Compilers and Options
=====================

   Some systems require unusual options for compilation or linking that
the `configure' script does not know about.  You can give `configure'
initial values for variables by setting them in the environment.  Using
a Bourne-compatible shell, you can do that on the command line like
this:
     CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure

Or on systems that have the `env' program, you can do it like this:
     env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure


Compiling For Multiple Architectures
====================================

   You can compile the package for more than one kind of computer at the
same time, by placing the object files for each architecture in their
own directory.  To do this, you must use a version of `make' that
supports the `VPATH' variable, such as GNU `make'.  `cd' to the
directory where you want the object files and executables to go and run
the `configure' script.  `configure' automatically checks for the
source code in the directory that `configure' is in and in `..'.

   If you have to use a `make' that does not supports the `VPATH'
variable, you have to compile the package for one architecture at a time
in the source code directory.  After you have installed the package for
one architecture, use `make distclean' before reconfiguring for another
architecture.


Installation Names
==================

   By default, `make install' will install the package's files in
`/usr/local/bin', `/usr/local/man', etc.  You can specify an
installation prefix other than `/usr/local' by giving `configure' the
option `--prefix=PATH'.

   You can specify separate installation prefixes for
architecture-specific files and architecture-independent files.  If you
give `configure' the option `--exec-prefix=PATH', the package will use
PATH as the prefix for installing programs and libraries.
Documentation and other data files will still use the regular prefix.

   In addition, if you use an unusual directory layout you can give
options like `--bindir=PATH' to specify different values for particular
kinds of files.  Run `configure --help' for a list of the directories
you can set and what kinds of files go in them.

   If the package supports it, you can cause programs to be installed
with an extra prefix or suffix on their names by giving `configure' the
option `--program-prefix=PREFIX' or `--program-suffix=SUFFIX'.


Optional Features
=================

   Some packages pay attention to `--enable-FEATURE' options to
`configure', where FEATURE indicates an optional part of the package.
They may also pay attention to `--with-PACKAGE' options, where PACKAGE
is something like `gnu-as' or `x' (for the X Window System).  The
`README' should mention any `--enable-' and `--with-' options that the
package recognizes.

   For packages that use the X Window System, `configure' can usually
find the X include and library files automatically, but if it doesn't,
you can use the `configure' options `--x-includes=DIR' and
`--x-libraries=DIR' to specify their locations.

   Run `configure --help' for a list of the options you can set.

Basic Installation on Windows NT
==================

This is a source-code release and may require tweaking in order to build in
your environment.  We typically build using 'make' from the MKS Toolkit and
their command-line interface to the Microsoft Visual C++ compiler.  Because
the configure script may not run under NT, we provide Makefile.nt and
config.nt.  You should copy or rename Makefile.nt to "makefile", and copy or
rename config.nt to "config.h".  

At this time, you might want to peruse config.h to change any parameters that
need to be adjusted for your systems.  Most of these are a function of your
compiler, etc. and you probably won't need to change them.  However, the
definitions for GROUP_SERVER_HOST and GROUP_SERVER_DOMAIN may be important.
The file doc/group_services.3 describes mechanisms through which dataexchange
programs can locate other sources of data through the use of a server which
matches names to Hostname/IP pairs.  The name server itself (called the
GROUP_SERVER in dataexchange) must run at a well-known network address and all
the dataexchange programs which use it must agree on what address that is.  If
you are in the "gatech.edu" domain, we are running a group server on the
machine "marquesas.cc.gatech.edu".  These values are already encoded into the
config.h file and do not need to be changed.  However, that server will accept
connections only from machines inside "gatech.edu" (because we can't serve the
world).  So if you're an external user of dataexchange, you must run your own
group server (or know someone who does) to use the group services.  Two
characteristics of the group server are encoded in config.h, the machine it is
to run on (GROUP_SERVER_HOST) and the network domain it will accept
connections from (GROUP_SERVER_DOMAIN).  The latter affects only the
group_server itself and just provides a mechanism for limiting the load on
your nameserver.  If you're not worried about this for whatever reason, set
the GROUP_SERVER_DOMAIN to "".  However, you must set the GROUP_SERVER_HOST to
a reasonable value and make sure the group_server is actually running on that
host.  Group_server is written to make sure only one will run at a time, so
on Unix you may wish to run it regularly via cron.  The more frequent you make
the cron entry, the sooner group_services will come back up if your machine
crashes (or some bug kills the group server).

After all this do "make all".  We do not provide a project workspace or
makefile configuration for VC++.  You *might* be able to create a Makefile
Project under VC++ and use nmake to build DataExchange.  However, I've found
that nmake doesn't like curly brackets in Makefiles.  So you probably would
have to edit Makefile.nt to change the curly brackets to smooth parens.  Also,
at this time, we build an object library, not a DLL.

The files Makefile.nt and config.nt were generated by the configure.nt
configuration script.  Configure.nt is itself derived from the Unix
"configure" script through the action of the sed script unix_to_nt.sed.  We
are able to run configure.nt using KSH with the MKS tools.  Your mileage may
vary.  Other versions of ksh or sh may work more or less like Unix and
configure or configure.nt may work more or less well.

Before you build DataExchange, you must build PBIO.  Because the path
searching mechanisms don't work well in configure.nt, PBIO *must* be
accessible in ../pbio from the dataexchange build directory.
