The following is an example of the mmap(9E) entry point and how to support 32-bit and 64-bit applications with the same device driver.

struct data32 { int len; caddr32_t addr; }; struct data { int len; caddr_t addr; }; xxmmap(dev_t dev, off_t off, int prot) { struct data dtc; /* a local copy for clash resolution */ struct data *dp = (struct data *)shared_area; switch (ddi_model_convert_from(ddi_mmap_get_model())) { case DDI_MODEL_ILP32: { struct data32 *da32p; da32p = (struct data32 *)shared_area; dp = &dtc; dp->len = da32p->len; dp->address = da32->address; break; } case DDI_MODEL_NONE: break; } /* continues along using dp */ ... }