Opening and using a dummy device

GDDM V3R2 Base Application Programming Guide

Opening and using a dummy device

GDDM V3R2 Base Application Programming Guide
SC33-0867-01

When developing and testing a new program it may be convenient to do so without attaching it to the eventual target device. This is possible by requesting a dummy device at DSOPEN time. The "name" of the device must be set to ' ' (blank).


     NAME_LIST(1)=' ';    /* Set blank name to indicate dummy device */

     /*    DEVICE-ID  FAMILY  DEV_TOKEN  OPTIONS        WHICH DEVICE */
     CALL DSOPEN(11,    1,    'L79A3',  0,PROCOPT_LIST,  1,NAME_LIST );

No output is sent to such a device. It is merely a convenience that would allow, for instance, the generation of output for a 3279 display at a 3472-G (nonPS) terminal.

You must specify a device token for a dummy device. You cannot specify a device token of * to get GDDM to query the device characteristics itself because the target device isn't really there. The only way GDDM can know the device characteristics of a dummy device is by the DSOPEN passing a device token. An explicit device token is therefore compulsory.

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