Build fixes.
code review feeback, close open comment
Ensured various XPG7 stuff are declared properly in sys/stat.h (and cleanup)
New documentation for wcslen, wcsnlen, wcscasecmp (and friends), wcsdup.
Various other tweaks and markup improvements.

*** 19,28 ****
--- 19,29 ----
   * CDDL HEADER END
   */
  
  /*
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
+  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
   */
  
  /*      Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
  /*      Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T   */
  /*      All Rights Reserved     */
*** 468,489 ****
  #define _R3_STAT_VER    1       /* SVR3.0 stat */
  #define _STAT_VER       2       /* current version of stat */
  
  #endif  /* __i386 || (__i386_COMPAT && _KERNEL) */
  
! #if defined(__EXTENSIONS__) || \
!         (!defined(_STRICT_STDC) && !defined(__XOPEN_OR_POSIX))
!         /* || defined(_XPG7) */
! /* for use with futimens() and utimensat() */
  #define UTIME_NOW       -1L
  #define UTIME_OMIT      -2L
! #endif  /* defined(__EXTENSIONS__) ... */
  
  #if !defined(_KERNEL) || defined(_BOOT)
  
- #if defined(__STDC__)
- 
  #if !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2) || \
          defined(_XPG4_2) || defined(__EXTENSIONS__)
  extern int fchmod(int, mode_t);
  #endif /* !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2)... */
  
--- 469,485 ----
  #define _R3_STAT_VER    1       /* SVR3.0 stat */
  #define _STAT_VER       2       /* current version of stat */
  
  #endif  /* __i386 || (__i386_COMPAT && _KERNEL) */
  
! #if defined(_XPG7) || !defined(_STRICT_SYMBOLS)
  #define UTIME_NOW       -1L
  #define UTIME_OMIT      -2L
! #endif
  
  #if !defined(_KERNEL) || defined(_BOOT)
  
  #if !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2) || \
          defined(_XPG4_2) || defined(__EXTENSIONS__)
  extern int fchmod(int, mode_t);
  #endif /* !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2)... */
  
*** 502,559 ****
          defined(_ATFILE_SOURCE)
  extern int fstatat64(int, const char *, struct stat64 *, int);
  #endif /* defined (_ATFILE_SOURCE) */
  #endif
  
! #if defined(__EXTENSIONS__) || defined(_ATFILE_SOURCE) || \
!         (!defined(_STRICT_STDC) && !defined(__XOPEN_OR_POSIX))
!         /* || defined(_XPG7) */
  extern int mkdirat(int, const char *, mode_t);
  extern int mkfifoat(int, const char *, mode_t);
  extern int mknodat(int, const char *, mode_t, dev_t);
  extern int fchmodat(int, const char *, mode_t, int);
  extern int futimens(int, const struct timespec[2]);
  extern int utimensat(int, const char *, const struct timespec[2], int);
- #endif  /* defined(__EXTENSIONS__) ... */
- 
- #else /* !__STDC__ */
- 
- #if !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2) || \
-         defined(_XPG4_2) || defined(__EXTENSIONS__)
- extern int fchmod();
- #endif /* !defined(__XOPEN_OR_POSIX) || (_POSIX_C_SOURCE > 2)... */
- 
- extern int chmod();
- extern int mkdir();
- extern int mkfifo();
- extern mode_t umask();
- 
- /* transitional large file interfaces */
- #if     defined(_LARGEFILE64_SOURCE) && !((_FILE_OFFSET_BITS == 64) && \
-             !defined(__PRAGMA_REDEFINE_EXTNAME))
- extern int fstat64();
- extern int stat64();
- extern int lstat64();
- #if !defined(__XOPEN_OR_POSIX) || defined(__EXTENSIONS__) || \
-         defined(_ATFILE_SOURCE)
- extern int fstatat64();
- #endif /* defined (_ATFILE_SOURCE) */
  #endif
  
- #if defined(__EXTENSIONS__) || defined(_ATFILE_SOURCE) || \
-         (!defined(_STRICT_STDC) && !defined(__XOPEN_OR_POSIX))
-         /* || defined(_XPG7) */
- extern int mkdirat();
- extern int mkfifoat();
- extern int mknodat();
- extern int fchmodat();
- extern int futimens();
- extern int utimensat();
- #endif  /* defined(__EXTENSIONS__) ... */
- 
- #endif /* defined(__STDC__) */
- 
  #include <sys/stat_impl.h>
  
  #endif /* !defined(_KERNEL) */
  
  #ifdef  __cplusplus
--- 498,519 ----
          defined(_ATFILE_SOURCE)
  extern int fstatat64(int, const char *, struct stat64 *, int);
  #endif /* defined (_ATFILE_SOURCE) */
  #endif
  
! #if defined(_XPG7) || defined(_ATFILE_SOURCE) || !defined(_STRICT_SYMBOLS)
  extern int mkdirat(int, const char *, mode_t);
  extern int mkfifoat(int, const char *, mode_t);
  extern int mknodat(int, const char *, mode_t, dev_t);
  extern int fchmodat(int, const char *, mode_t, int);
+ #endif
+ 
+ #if defined(_XPG7) || !defined(_STRICT_SYMBOLS)
  extern int futimens(int, const struct timespec[2]);
  extern int utimensat(int, const char *, const struct timespec[2], int);
  #endif
  
  #include <sys/stat_impl.h>
  
  #endif /* !defined(_KERNEL) */
  
  #ifdef  __cplusplus