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

*** 27,36 ****
--- 27,40 ----
   * Copyright 1999-2003 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
   */
  
  /*
+  * Copyright 2014 PALO, Richard.
+  */
+ 
+ /*
   * An application should not include this header directly.  Instead it
   * should be included only through the inclusion of other Sun headers.
   *
   * The contents of this header is limited to identifiers specified in the
   * C Standard.  Any new identifiers specified in future amendments to the
*** 41,70 ****
   */
  
  #ifndef _ISO_STDDEF_ISO_H
  #define _ISO_STDDEF_ISO_H
  
- #pragma ident   "%Z%%M% %I%     %E% SMI" /* SVr4.0 1.5 */
- 
  #include <sys/isa_defs.h>
  
  #ifdef  __cplusplus
  extern "C" {
  #endif
  
  #if __cplusplus >= 199711L
  namespace std {
  #endif
  
- #ifndef NULL
- #if defined(_LP64)
- #define NULL    0L
- #else
- #define NULL    0
- #endif
- #endif
- 
  #if !defined(_PTRDIFF_T) || __cplusplus >= 199711L
  #define _PTRDIFF_T
  #if defined(_LP64) || defined(_I32LPx)
  typedef long    ptrdiff_t;              /* pointer difference */
  #else
--- 45,65 ----
   */
  
  #ifndef _ISO_STDDEF_ISO_H
  #define _ISO_STDDEF_ISO_H
  
  #include <sys/isa_defs.h>
+ #include <sys/null.h>
  
  #ifdef  __cplusplus
  extern "C" {
  #endif
  
  #if __cplusplus >= 199711L
  namespace std {
  #endif
  
  #if !defined(_PTRDIFF_T) || __cplusplus >= 199711L
  #define _PTRDIFF_T
  #if defined(_LP64) || defined(_I32LPx)
  typedef long    ptrdiff_t;              /* pointer difference */
  #else