* cygheap.h (struct cwdstuff): Remove sync member and keep_in_sync

accessors.
	* external.cc (cygwin_internal): Drop call to cygheap->cwd.keep_in_sync.
	* fhandler_disk_file.cc (fhandler_disk_file::link): Always presume
	ability to create hard links.
	* path.cc (cwdstuff::init): Drop 9x considerations.
	(cwdstuff::keep_in_sync): Remove.
	(cwdstuff::set): Take NT for granted.
	* pinfo.h (cygwin_pid): Just return pid.
	* wincap.cc: Remove has_hard_links, can_open_directories,
	has_negative_pids, has_named_pipes, has_try_enter_critical_section,
	cant_debug_dll_entry and detect_win16_exe throughout.
	* wincap.h: Ditto.

winsup/cygwin/cygheap.h

@@ -225,7 +225,6 @@ struct cwdstuff
   char *win32;
   DWORD hash;
   DWORD drive_length;
-  bool sync;
   static muto cwd_lock;
   char *get (char *, int = 1, int = 0, unsigned = CYG_MAX_PATH);
   DWORD get_hash ();
@@ -240,8 +239,6 @@ struct cwdstuff
   void fixup_after_exec (char *, char *, DWORD);
   bool get_initial ();
   int set (const char *, const char *, bool);
-  bool keep_in_sync () const { return sync; }
-  void keep_in_sync (bool val);
 };
 
 #ifdef DEBUGGING