Capturing Data from Host Screens

A common automation task is to control the way data from host screens appears to the end user. You typically accomplish this by copying selected data from the host screen to your application, and vice versa. This topic describes the Screen object and the key methods used to copy screen information.

Screen Object

Interacting with a host session requires the Screen object that is specific to the type of host you are using:

This Screen object
ScreenTn3270 An IBM mainframe host session.
ScreenTn5250 An IBM AS/400 host session.
ScreenT27 A Unisys ClearPath LX, ClearPath NX, or A Series host session.
ScreenUts A Unisys ClearPath IX or 2200 Series host session.
ScreenVt A DEC VAX, Linux, or UNIX host session.
ScreenAlc A Unisys or IBM host session using the Airline Protocol.

For information on how to specify a screen object, see Defining an XML Configuration and Requesting a Screen Object.

Key Methods Used

The following Screen object methods are commonly used for copying data between a presentation space and your application:

Method Description
putString Copies data to a specified position in the host presentation space.
getString Copies data from a specified position in the host presentation space.
sendKeys Transmits characters and keystrokes to the host session.
Pause processing for a specified number of milliseconds until a condition is met. Because of varying host and network speeds, these screen methods help to prevent timing errors.
Related Topics
Common Tasks
The Screen Object Model
Keystroke Reference