Mass checkin (more to follow for other directories).

Introduce truly separate (sub)interpreter objects.  For now, these
must be used by separate threads, created from C.  See Demo/pysvr for
an example of how to use this.  This also rationalizes Python's
initialization and finalization behavior:

Py_Initialize() -- initialize the whole interpreter
Py_Finalize() -- finalize the whole interpreter

tstate = Py_NewInterpreter() -- create a new (sub)interpreter
Py_EndInterpreter(tstate) -- delete a new (sub)interpreter

There are also new interfaces relating to threads and the interpreter
lock, which can be used to create new threads, and sometimes have to
be used to manipulate the interpreter lock when creating or deleting
sub-interpreters.  These are only defined when WITH_THREAD is defined:

PyEval_AcquireLock() -- acquire the interpreter lock
PyEval_ReleaseLock() -- release the interpreter lock

PyEval_AcquireThread(tstate) -- acquire the lock and make the thread current
PyEval_ReleaseThread(tstate) -- release the lock and make NULL current

Other administrative changes:

- The header file bltinmodule.h is deleted.

- The init functions for Import, Sys and Builtin are now internal and
  declared in pythonrun.h.

- Py_Setup() and Py_Cleanup() are no longer declared.

- The interpreter state and thread state structures are now linked
  together in a chain (the chain of interpreters is a static variable
  in pythonrun.c).

- Some members of the interpreter and thread structures have new,
  shorter, more consistent, names.

- Added declarations for _PyImport_{Find,Fixup}Extension() to import.h.
diff --git a/Include/Python.h b/Include/Python.h
index 96fc1f4..9a18e2d 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -95,7 +95,6 @@
 #include "sysmodule.h"
 #include "intrcheck.h"
 #include "import.h"
-#include "bltinmodule.h"
 
 #include "abstract.h"
 
diff --git a/Include/bltinmodule.h b/Include/bltinmodule.h
deleted file mode 100644
index 66bb165..0000000
--- a/Include/bltinmodule.h
+++ /dev/null
@@ -1,47 +0,0 @@
-#ifndef Py_BLTINMODULE_H
-#define Py_BLTINMODULE_H
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/***********************************************************
-Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
-The Netherlands.
-
-                        All Rights Reserved
-
-Permission to use, copy, modify, and distribute this software and its
-documentation for any purpose and without fee is hereby granted,
-provided that the above copyright notice appear in all copies and that
-both that copyright notice and this permission notice appear in
-supporting documentation, and that the names of Stichting Mathematisch
-Centrum or CWI or Corporation for National Research Initiatives or
-CNRI not be used in advertising or publicity pertaining to
-distribution of the software without specific, written prior
-permission.
-
-While CWI is the initial source for this software, a modified version
-is made available by the Corporation for National Research Initiatives
-(CNRI) at the Internet address ftp://ftp.python.org.
-
-STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
-REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
-MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
-CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
-DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
-PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
-TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-PERFORMANCE OF THIS SOFTWARE.
-
-******************************************************************/
-
-/* Built-in module interface */
-
-extern void PyBuiltin_Init Py_PROTO((void));
-extern PyObject *PyBuiltin_GetDict Py_PROTO(());
-extern PyObject *PyBuiltin_GetModule Py_PROTO(());
-
-#ifdef __cplusplus
-}
-#endif
-#endif /* !Py_BLTINMODULE_H */
diff --git a/Include/ceval.h b/Include/ceval.h
index cc4c4d8..2805379 100644
--- a/Include/ceval.h
+++ b/Include/ceval.h
@@ -105,6 +105,8 @@
 #ifdef WITH_THREAD
 
 extern void PyEval_InitThreads Py_PROTO((void));
+extern void PyEval_AcquireLock Py_PROTO((void));
+extern void PyEval_ReleaseLock Py_PROTO((void));
 extern void PyEval_AcquireThread Py_PROTO((PyThreadState *tstate));
 extern void PyEval_ReleaseThread Py_PROTO((PyThreadState *tstate));
 
diff --git a/Include/import.h b/Include/import.h
index 4ddbd4c..f5fa9bb 100644
--- a/Include/import.h
+++ b/Include/import.h
@@ -37,7 +37,6 @@
 
 /* Module definition and import interface */
 
-void PyImport_Init Py_PROTO((void));
 long PyImport_GetMagicNumber Py_PROTO((void));
 PyObject *PyImport_ExecCodeModule Py_PROTO((char *name, PyObject *co));
 PyObject *PyImport_GetModuleDict Py_PROTO((void));
@@ -47,6 +46,9 @@
 void PyImport_Cleanup Py_PROTO((void));
 int PyImport_ImportFrozenModule Py_PROTO((char *));
 
+extern PyObject *_PyImport_FindExtension Py_PROTO((char *, char *));
+extern PyObject *_PyImport_FixupExtension Py_PROTO((char *, char *));
+
 struct _inittab {
 	char *name;
 	void (*initfunc)();
diff --git a/Include/pystate.h b/Include/pystate.h
index b660ff8..ad91426 100644
--- a/Include/pystate.h
+++ b/Include/pystate.h
@@ -42,15 +42,19 @@
 
 #define NEXITFUNCS 32
 
+struct _ts; /* Forward */
+struct _is; /* Forward */
+
 typedef struct _is {
 
-	PyObject *import_modules;
+	struct _is *next;
+	struct _ts *tstate_head;
+
+	PyObject *modules;
 	PyObject *sysdict;
+	PyObject *builtins;
 
-	int nthreads;
-
-	void (*exitfuncs[NEXITFUNCS])();
-	int nexitfuncs;
+	int checkinterval;
 
 } PyInterpreterState;
 
@@ -61,7 +65,8 @@
 
 typedef struct _ts {
 
-	PyInterpreterState *interpreter_state;
+	struct _ts *next;
+	PyInterpreterState *interp;
 
 	struct _frame *frame;
 	int recursion_depth;
@@ -70,7 +75,6 @@
 
 	PyObject *sys_profilefunc;
 	PyObject *sys_tracefunc;
-	int sys_checkinterval;
 
 	PyObject *curexc_type;
 	PyObject *curexc_value;
@@ -80,54 +84,22 @@
 	PyObject *exc_value;
 	PyObject *exc_traceback;
 
-	/* XXX Other state that should be here:
-	   - signal handlers
-	   - low-level "pending calls"
-	   Problem with both is that they may be referenced from
-	   interrupt handlers where there is no clear concept of a
-	   "current thread"???
-	*/
+	/* XXX signal handlers should also be here */
 
 } PyThreadState;
 
 
 PyInterpreterState *PyInterpreterState_New Py_PROTO((void));
+void PyInterpreterState_Clear Py_PROTO((PyInterpreterState *));
 void PyInterpreterState_Delete Py_PROTO((PyInterpreterState *));
 
 PyThreadState *PyThreadState_New Py_PROTO((PyInterpreterState *));
+void PyThreadState_Clear Py_PROTO((PyThreadState *));
 void PyThreadState_Delete Py_PROTO((PyThreadState *));
 
 PyThreadState *PyThreadState_Get Py_PROTO((void));
 PyThreadState *PyThreadState_Swap Py_PROTO((PyThreadState *));
 
-/* Some background.
-
-   There are lots of issues here.
-
-   First, we can build Python without threads, with threads, or (when
-   Greg Stein's mods are out of beta, on some platforms) with free
-   threading.
-
-   Next, assuming some form of threading is used, there can be several
-   kinds of threads.  Python code can create threads with the thread
-   module.  C code can create threads with the interface defined in
-   python's "thread.h".  Or C code can create threads directly with
-   the OS threads interface (e.g. Solaris threads, SGI threads or
-   pthreads, whatever is being used, as long as it's the same that
-   Python is configured for).
-
-   Next, let's discuss sharing of interpreter state between threads.
-   The exception state (sys.exc_* currently) should never be shared
-   between threads, because it is stack frame specific.  The contents
-   of the sys module, in particular sys.modules and sys.path, are
-   generally shared between threads.  But occasionally it is useful to
-   have separate module collections, e.g. when threads originate in C
-   code and are used to execute unrelated Python scripts.
-   (Traditionally, one would use separate processes for this, but
-   there are lots of reasons why threads are attractive.)
-
-*/
-
 #ifdef __cplusplus
 }
 #endif
diff --git a/Include/pythonrun.h b/Include/pythonrun.h
index ae33624..1f8093e 100644
--- a/Include/pythonrun.h
+++ b/Include/pythonrun.h
@@ -40,8 +40,9 @@
 void Py_SetProgramName Py_PROTO((char *));
 char *Py_GetProgramName Py_PROTO((void));
 
-void Py_Setup Py_PROTO((void));
 void Py_Initialize Py_PROTO((void));
+PyThreadState *Py_NewInterpreter Py_PROTO((void));
+void Py_EndInterpreter Py_PROTO((PyThreadState *));
 
 int PyRun_AnyFile Py_PROTO((FILE *, char *));
 
@@ -64,11 +65,6 @@
 
 void Py_Exit Py_PROTO((int));
 
-void Py_Cleanup Py_PROTO((void));
-
-void PyImport_Init	Py_PROTO((void));
-void PyBuiltin_Init	Py_PROTO((void));
-
 int Py_FdIsInteractive Py_PROTO((FILE *, char *));
 
 /* In getpath.c */
@@ -84,6 +80,12 @@
 const char *Py_GetCompiler Py_PROTO((void));
 const char *Py_GetBuildInfo Py_PROTO((void));
 
+/* Internal -- various one-time initializations */
+
+PyObject *_PyBuiltin_Init Py_PROTO((void));
+PyObject *_PySys_Init Py_PROTO((void));
+void _PyImport_Init Py_PROTO((void));
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/Include/sysmodule.h b/Include/sysmodule.h
index 7761361..424dc87 100644
--- a/Include/sysmodule.h
+++ b/Include/sysmodule.h
@@ -40,7 +40,6 @@
 PyObject *PySys_GetObject Py_PROTO((char *));
 int PySys_SetObject Py_PROTO((char *, PyObject *));
 FILE *PySys_GetFile Py_PROTO((char *, FILE *));
-void PySys_Init Py_PROTO((void));
 void PySys_SetArgv Py_PROTO((int, char **));
 void PySys_SetPath Py_PROTO((char *));