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Introduction

The E787 Data Distributor (DD) is a UNIX based event buffer manager, originally developed for the AGS rare kaon experiment E787. It is written entirely in C and currently runs on SGI and HP.

It allows to distribute events to processes in real time in a multiprocessor environment for data reduction, event building, online event analysis and monitoring. The bookkeeping is done with a software implementation of FIFOs (first in, first out) using shared memory and semaphores.

In the following sections we first describe the philosophy of DD system. Its use in the E787 experiment is as an example on how to implement it in HEP experiments.
In the second section we describe the routines that are relevant for the user, followed by a section in which a few typical example programs are presented.
Chapter 5 describes how the user can customize the DD system, followed by a section on the user interface. The network connection of the DD system is under complete revision and its description is (temporarily) omitted.
The last section is a list of FAQ.



Online software development
Thu Mar 14 10:35:53 EST 1996