Device dependence in GDDM application programs

GDDM V3R2 Base Application Programming Guide

Device dependence in GDDM application programs

GDDM V3R2 Base Application Programming Guide
SC33-0867-01

GDDM provides much of its function in a device-independent way. However, there are two ways that some GDDM functions are affected when programs invoke them for particular devices.

Device variation

An API call and its parameters are valid, but the current device does not give the same results as the general case usually described in this guide.

GDDM aims to exploit the capabilities of many different devices, so relatively few devices support the full range of parameter values for many calls. Using GSCOL to set the current color of an area to orange on an eight-color display is such a case.

Device dependence

The program issues an API call that is only valid for a particular device or group of devices. If the current device is not one of these, a GDDM error message is displayed.

Attempting to use alphanumerics on a plotter is a case in point.

The information in this topic is aimed to make you aware of potential situations in the first category, and to help you avoid or cope with situations in the second.

Notices | Terms of use | Support | Contact z/OS