5218 posix definition of NULL
correct unistd.h and iso/stddef_iso.h
update gate source affected

*** 380,390 ****
          char KS[16][48];
   
          for(i=0; i<66; i++)
                  block[i] = 0;
          /* Solaris Kerberos */
!         for(i=0; ((c= *pw) != NULL) && i<64; pw++){
                  for(j=0; j<7; j++, i++)
                          block[i] = (c>>(6-j)) & 01;
                  i++;
          }
          
--- 380,390 ----
          char KS[16][48];
   
          for(i=0; i<66; i++)
                  block[i] = 0;
          /* Solaris Kerberos */
!         for(i=0; ((c= *pw) != 0) && i<64; pw++){
                  for(j=0; j<7; j++, i++)
                          block[i] = (c>>(6-j)) & 01;
                  i++;
          }