shadow5.0

Short:        Concurrent, object-oriented library. OS 2.0
Type:         os20/util
Architecture: m68k-amigaos

SHADOW.library V5.0 Released:13 Nov 1992 by David C. Navas
Update to SHADOW V4.8

Freely distributable only for those environments which are
themselves freely distributable.

Includes shadow.library, ppipc.library, and two example programs
with source.

Also included is about 500k of Documentation!

Requires AmigaDOS2.0!!!

Taken from Shadow/Docs/Introduction.doc:

          SHADOW is a concurrent-object-oriented addition to AmigaDOS.
     Its principle design goal is to help standardize an extensible
     environment paradigm.  It takes advantage of some of the better
     AmigaDOS facilities (shared memory system, IPC ports, and fast
     context switching) by internally managing much of the inter-task
     communications, resource tracking, and resource allocation.

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          SHADOW was created to solve the problems which I ran into with
     my first programming project -- JazzBench.  That experience taught
     me that the most important thing in a co-operative multi-program
     environment is flexibility.  You need to be able to change the
     behaviour of EVERYTHING -as- -it- -runs-.  This lesson was the
     principle reason behind the initial design of SHADOW, and the result
     of that principle was the entire WatchedVariable construct. To a
     lesser extent, it was also responsible for Patches.

          However, that was not the only lesson that was learned.  Trying
     to locate governing control within a single server not only created
     bottleneck problems, but also, in the end, either limited or
     complicated the design process for my programs.  What I needed was a
     subsystem which effectively dealt with the concurrency and shared
     resource management problems across a distributed environment.

          The other major subsystems of SHADOW support the increased use
     of more complicated data structures.  Exec lists are very fast at
     some things, but searching and sorting are definitely not their
     strong points.