Conversion image

A conversion image is a data set that contains the information that z/OS® Unicode Services needs when performing character and case conversions. The conversion image defines which conversion tables z/OS is to load and use for these conversions.

You create a conversion image by invoking the z/OS Unicode Services image generator when you set up z/OS Unicode Services. The image generator creates the conversion image according to what you specify in the SYSIN DD statement in the job that invokes the image generator, CUNJIUTL. The generated image is stored in the data set that is identified in the SYSIMG DD statement. Messages from this process are listed in the data set that is identified by the SYSPRINT DD statement.

You can activate a conversion image during IPL or by issuing the z/OS SET UNI or SETUNI system command.

If you have z/OS 1.7 or later, conversions are loaded on request. However, to avoid waiting while conversion tables are loaded, you can create your own conversion image.

You can create more than one conversion image. These images are kept in different data sets. Use the SET UNI or SETUNI command to merge these images into the existing z/OS Unicode Services conversion image. Any tables in the new image that intersect with tables in the existing image are not loaded.

You can add, delete, or replace conversion images by using the SET UNI or SETUNI command.