> ## 1 Introduction

> The Event Tracer (ET) uses the built-in trace mechanism in Erlang and provides tools for collection and graphical viewing of trace data.

> The viewed trace data is normally collected from Erlang trace ports or files.

> ### 1.1 Scope and Purpose

> This manual describes the Event Tracer (ET) appliacation, as a component of the Erlang/Open Telecom Platform development environment. It is assumed that the reader is familiar with the Erlang Development Environment, which is described in a separate User's Guide.

> ### 1.2 Prerequisites

> The following prerequisites is required for understanding the material in the Event Tracer (ET) User's Guide:

> - familiarity with the Erlang system and Erlang programming in general and the especially the art of Erlang tracing.

> The application requires Erlang/OTP release R7B or later.

> ### 1.3 About This Manual

> In addition to this introductory chapter, the Megaco User's Guide contains the following chapters:

> - Chapter 2: "Usage" describes the architecture and typical usage of the application.
> - Chapter 3: "Examples" gives some usage examples

> ### 1.4 Where to Find More Information

> Refer to the following documentation for more information about Event Tracer (ET) and about the Erlang/OTP development system:

> - the Reference Manual of the `Event Tracer (ET)`/p>
> - documentation of basic tracing in `erlang:trace/4` and `erlang:trace_pattern/3` and then the utilities derived from these: `dbg`, `observer` and `et`.
> - Concurrent Programming in Erlang, 2nd Edition (1996), Prentice-Hall, ISBN 0-13-508301-X.

Copyright © 1991-2003 Ericsson Utvecklings AB