About This Book
The InterSystems Callout Gateway (implemented in the Caché $ZF functions) allows you to invoke external programs and system services from Caché. It also provides a way to integrate your custom code into Caché.
This book addresses the following topics:
Introduction — introduces concepts important to understanding the rest of this book, summarizes the capabilities of the InterSystems Callout Gateway, and provides links to other resources.
Running Programs or System Commands with $ZF(-100) — describes how to use a $ZF option that provides functionality similar to a command line interface.
Creating an InterSystems Callout Library — describes how to create a Callout shared library with functions that can be invoked from Caché. Code can be written in any language that supports C/C++ calling conventions.
Invoking Callout Library Functions — describes how to call functions dynamically from a Callout shared library.
Statically Linked Callout Functions — describes how to create a customized version of Caché that includes your Callout functions.
Special Considerations for UNIX® — discusses issues relevant only to UNIX® and related operating systems.
InterSystems Callout Quick Reference — provides a detailed description of each $ZF function.
For a detailed outline, see the Table of Contents.
For general information, see Using InterSystems Documentation.