char *tmpaddr;
        char *lowest;
 
-       for(i=0; thislist[i].theres_more != 0; i++) {
+       for(i=0; thislist[i].theres_more; i++) {
                lowest = thislist[i].start_adr;
-               for(mitr = i+1; thislist[mitr-1].theres_more != 0; mitr++)
+               for(mitr = i+1; thislist[mitr-1].theres_more; mitr++)
                        if(thislist[mitr].start_adr < lowest) {
                                lowest = thislist[mitr].start_adr;
                                swapi = mitr;
                        prom_phys_total[iter].num_bytes = mptr->num_bytes;
                        prom_phys_total[iter].theres_more = &prom_phys_total[iter+1];
                }
-               prom_phys_total[iter-1].theres_more = 0x0;
+               prom_phys_total[iter-1].theres_more = NULL;
                /* Second, the total prom taken descriptors. */
                for(mptr = (*(romvec->pv_v0mem.v0_prommap)), iter=0;
                    mptr; mptr=mptr->theres_more, iter++) {
                        prom_prom_taken[iter].num_bytes = mptr->num_bytes;
                        prom_prom_taken[iter].theres_more = &prom_prom_taken[iter+1];
                }
-               prom_prom_taken[iter-1].theres_more = 0x0;
+               prom_prom_taken[iter-1].theres_more = NULL;
                /* Last, the available physical descriptors. */
                for(mptr = (*(romvec->pv_v0mem.v0_available)), iter=0;
                    mptr; mptr=mptr->theres_more, iter++) {
                        prom_phys_avail[iter].num_bytes = mptr->num_bytes;
                        prom_phys_avail[iter].theres_more = &prom_phys_avail[iter+1];
                }
-               prom_phys_avail[iter-1].theres_more = 0x0;
+               prom_phys_avail[iter-1].theres_more = NULL;
                /* Sort all the lists. */
                prom_sortmemlist(prom_phys_total);
                prom_sortmemlist(prom_prom_taken);
                        prom_phys_avail[iter].theres_more =
                                &prom_phys_avail[iter+1];
                }
-               prom_phys_avail[iter-1].theres_more = 0x0;
+               prom_phys_avail[iter-1].theres_more = NULL;
 
                num_regs = prom_getproperty(node, "reg",
                                            (char *) prom_reg_memlist,
                        prom_phys_total[iter].theres_more =
                                &prom_phys_total[iter+1];
                }
-               prom_phys_total[iter-1].theres_more = 0x0;
+               prom_phys_total[iter-1].theres_more = NULL;
 
                node = prom_getchild(prom_root_node);
                node = prom_searchsiblings(node, "virtual-memory");
                        prom_prom_taken[iter].theres_more =
                                &prom_prom_taken[iter+1];
                }
-               prom_prom_taken[iter-1].theres_more = 0x0;
+               prom_prom_taken[iter-1].theres_more = NULL;
 
                prom_sortmemlist(prom_prom_taken);
 
        case PROM_SUN4:
 #ifdef CONFIG_SUN4     
                /* how simple :) */
-               prom_phys_total[0].start_adr = 0x0;
+               prom_phys_total[0].start_adr = NULL;
                prom_phys_total[0].num_bytes = *(sun4_romvec->memorysize);
-               prom_phys_total[0].theres_more = 0x0;
-               prom_prom_taken[0].start_adr = 0x0; 
+               prom_phys_total[0].theres_more = NULL;
+               prom_prom_taken[0].start_adr = NULL; 
                prom_prom_taken[0].num_bytes = 0x0;
-               prom_prom_taken[0].theres_more = 0x0;
-               prom_phys_avail[0].start_adr = 0x0;
+               prom_prom_taken[0].theres_more = NULL;
+               prom_phys_avail[0].start_adr = NULL;
                prom_phys_avail[0].num_bytes = *(sun4_romvec->memoryavail);
-               prom_phys_avail[0].theres_more = 0x0;
+               prom_phys_avail[0].theres_more = NULL;
 #endif
                break;