* Makefile.in: Build wincap.o.

* wincap.cc: New file.
        * wincap.h: Ditto.
        * autoload.cc: Add dynamic load statement for `CreateHardLinkA'.
        * dcrt0.cc (os_being_run): Eliminated.
        (osname): Ditto.
        (iswinnt): Ditto.
        (set_os_type): Ditto.
        (dll_crt0_1): Call wincap.init() instead of set_os_type().
        (_dll_crt0): Ditto.
        * environ.cc (set_chunksize): New function.
        (parse_thing): `forkchunk' setting now invokes function `set_chunksize'.
        * fork.cc (chunksize): Eliminated. Moved to be member of wincap.
        * host_dependent.h: Removed.
        * syscalls.cc (_link): Try using `CreateHardLinkA' first, if available.
        * cygheap.cc, dcrt0.cc, delqueue.cc, dir.cc,
        environ.cc, fhandler.cc, fhandler.h, fhandler_console.cc,
        fhandler_mem.cc, fork.cc, mmap.cc, net.cc, pinfo.cc, pinfo.h,
        security.cc, syscalls.cc, sysconf.cc, syslog.cc, thread.cc,
        times.cc, tty.cc, uinfo.cc, uname.cc, winsup.h: Use new wincap
        capability check throughout.
        * winsup.h: Include wincap.h. Eliminate extern declarations of
        `os_being_run' and `iswinnt'. Eliminate `os_type" definition.
        * include/cygwin/version.h: Bump version to 1.3.4.

winsup/cygwin/fhandler_mem.cc

@@ -28,7 +28,7 @@ fhandler_dev_mem::fhandler_dev_mem (const char *name, int nunit)
   unit (nunit)
 {
   /* Reading physical memory only supported on NT/W2K. */
-  if (!iswinnt)
+  if (!wincap.has_physical_mem_access ())
     {
       mem_size = 0;
       return;
@@ -74,7 +74,7 @@ fhandler_dev_mem::~fhandler_dev_mem (void)
 int
 fhandler_dev_mem::open (const char *, int flags, mode_t)
 {
-  if (!iswinnt)
+  if (!wincap.has_physical_mem_access ())
     {
       set_errno (ENOENT);
       debug_printf ("%s is accessible under NT/W2K only",
@@ -413,7 +413,7 @@ fhandler_dev_mem::fstat (struct stat *buf)
 
   memset (buf, 0, sizeof *buf);
   buf->st_mode = S_IFCHR;
-  if (!iswinnt)
+  if (!wincap.has_physical_mem_access ())
     buf->st_mode |= S_IRUSR | S_IWUSR |
 		    S_IRGRP | S_IWGRP |
 		    S_IROTH | S_IWOTH;