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. . . . 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.