* configure.in: Remove NEWVFORK default.

* configure: Regenerate.
* dcrt0.cc: Conditionalize vfork stuff throughout.
* dtable.cc: Ditto.
* perthread.h: Ditto.
* pipe.cc (fhandler_pipe::close): Ditto.
* spawn.cc (spawnve): Ditto.
* syscalls.cc (setsid): Ditto.
* exceptions.cc (sigpacket::process): Use macro to refer to vfork pid.
* debug.cc (verify_handle): Define new function.
* debug.h (VerifyHandle): Define new macro.
(verify_handle): Declare new function
* fhandler.cc (fhandler_base::dup): Verify that dup'ed handle is not supposed
to be in use.
(fhandler_base::set_inheritance): Ditto.
(fhandler_base::fork_fixup): Ditto.
* fhandler_socket.cc (fhandler_socket::dup): Ditto.
* fhandler_tty.cc (fhandler_tty_slave::open): Ditto.
* net.cc (set_socket_inheritance): Ditto.
* pinfo.cc (pinfo_fixup_after_exec): Ditto.
* sigproc.cc (proc_subproc): Ditto.
(sig_send): Ditto.
* spawn.cc (spawn_guts): Ditto.
* thread.cc (pthread::init_mainthread): Ditto.
* pipe.cc (fhandler_pipe::close): Close read_state with ForceCloseHandle since
it was protected.
(fhandler_pipe::fixup_after_exec): Protect read_state handle.
(fhandler_pipe::dup): Correctly close open handles on error condition.  Verify
that dup'ed handle is not supposed to be in use.
(fhandler_pipe::create): Protect read_state.

winsup/cygwin/perthread.h

@@ -43,8 +43,14 @@ public:
   size_t size () {return sizeof (waitq);}
 };
 
-#if defined (NEED_VFORK)
+#ifdef NEED_VFORK
 #include "cygtls.h"
+#endif
+
+#ifndef NEWVFORK
+#define VFORKPID 0
+#else
+#if defined (NEED_VFORK)
 class vfork_save
 {
   jmp_buf j;
@@ -82,7 +88,9 @@ public:
 };
 extern per_thread_vfork vfork_storage;
 extern vfork_save *main_vfork;
+#define VFORKPID main_vfork->pid
 #endif
+#endif /*NEWVFORK*/
 
 extern per_thread_waitq waitq_storage;