The WinRegisterObjectClass function registers a workplace object class.

#define INCL_WINWORKPLACE
#include <os2.h>

PSZ     pClassName;  /*  A pointer to object class being registered. */
PSZ     pModname;    /*  A pointer to DLL name. */
BOOL    rc;          /*  Success indicator. */

rc = WinRegisterObjectClass(pClassName, pModname);