PDB Frequently Asked Questions (FAQ)

Last-Modified:     October 11, 1994



Welcome to the FAQ for PDB!

INTRODUCTION
PDB is a small part of a much bigger effort called PACT. PACT is
the portable environment and toolkit that we use to create portable 
applications, and to create functionality not readily available. 
PACT is our environment of choice for handling unique data,
portable computing environments, and the distributed computing 
arenas; and for converting data for the visualization application 
or algorithm of choice. We have created PACT to shield ourselves 
from new software, and hardware so we can concentrate on the 
applications at hand. PACT is beginning to emphasize design that 
takes advantage of massively parallel environments.

We would like to hear of your experiences with PACT. And, we would 
be especially pleased to try to add your mathematical, graphical, 
or other functionality to future distributions of PACT. 

NOTICE
Absolute portability is our GOAL! Most of the time we install PACT 
without problems, the other times take varying amounts of effort to 
track down. Usually the problems are simple, such as missing 
headers. If your experience with PACT is not absolute portability, 
we would like to hear from you so we can try to make it so. Please 
direct all portability issues to:

     sabrown@phoenix.ocf.llnl.gov


Thanks to all who have contributed to this FAQ.  Corrections and 
contributions always welcome. Please e-mail comments, additions, 
and corrections to:

                  dpact@rugrat.llnl.gov 

and use SUBJECT: PDB FAQ

Items needing more input from you and others are marked with a ???.

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TABLE OF CONTENTS
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1) What is PDB?
2) What is PACT?
3) Where can I get the complete PDB source and documentation?
4) ???

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1) What is PDB?

   PDB is a system for handling binary data in a portable way.
   It can move data between files and memory and (with PPC) between
   processes. In contrast to other systems which aim at FORTRAN
   level functionality, PDB supports programmers in using natural
   C idioms (this also covers FORTRAN as a subset).

     a) Self-describing files
     b) Efficient conversion scheme (not XDR based)
     c) Uses C model for data typing and meaning
     d) Supports user defined structures
     e) Supports use of pointers in data trees
     f) File variables can be appended to (indefinite dimension)
     g) Partial reads and writes
     h) Supports row major or column major ordering
     i) Primitives support accessing other file types

2) What is PACT?

   PACT stands for Portable Application Code Toolkit. It is a
   self-contained set of tools which support developing and
   using portable programs particularly scientific and engineering
   applications.  See the pact.FAQ

3) Where can I get the complete PDB source and documentation?

Since PDB is an intimate part of PACT, this will get the complete PACT including PDB. You may selectively install PDB.

Please use ftp to 
          phoenix.ocf.llnl.gov 
                    or
           134.9.48.6
log in as anonymous, using your email address for the password, 
cd pub - to change directory,
binary - to set the transfer mode,
get the three pact files (the date indicates the update - check for updates):
          pact.README
          pact10_28_93-doc.tar.Z
          pact10_28_93-src

The pact.README file describes the PACT installation process. 

4) ???