Displays information about data structures related to Write Bitmap (WBM). Bitmaps are used by Host-Base Volume Shadowing (HBVS) for the implementation of Mini Copy and Host-Based Minimerge (HBMM). If the /BITMAP qualifier is specified with a device that is not an HBVS virtual unit, the error NOSUCHDEV is returned. A device name must be specified. If SHOW DEVICE/BITMAP DS is entered, bitmaps for all HBVS virtual units are displayed.