* Makefile adapted to changes below.
* split pythonmain.c in two: most stuff goes to pythonrun.c, in the library.
* new optional built-in threadmodule.c, build upon Sjoerd's thread.{c,h}.
* new module from Sjoerd: mmmodule.c (dynamically loaded).
* new module from Sjoerd: sv (svgen.py, svmodule.c.proto).
* new files thread.{c,h} (from Sjoerd).
* new xxmodule.c (example only).
* myselect.h: bzero -> memset
* select.c: bzero -> memset; removed global variable
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
new file mode 100644
index 0000000..2a68f24
--- /dev/null
+++ b/Python/pythonrun.c
@@ -0,0 +1,424 @@
+/***********************************************************
+Copyright 1991, 1992 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 not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM 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.
+
+******************************************************************/
+
+/* Python interpreter top-level routines, including init/exit */
+
+#include "allobjects.h"
+
+#include "grammar.h"
+#include "node.h"
+#include "parsetok.h"
+#include "graminit.h"
+#include "errcode.h"
+#include "sysmodule.h"
+#include "compile.h"
+#include "ceval.h"
+#include "pythonrun.h"
+#include "import.h"
+
+#ifdef USE_THREAD
+extern void *save_thread();
+#endif
+
+extern char *getpythonpath();
+
+extern grammar gram; /* From graminit.c */
+
+int debugging; /* Needed by parser.c */
+int verbose; /* Needed by import.c */
+
+/* Initialize all */
+
+void
+initall()
+{
+	static int inited;
+	
+	if (inited)
+		return;
+	inited = 1;
+	
+	initimport();
+	
+	/* Modules 'builtin' and 'sys' are initialized here,
+	   they are needed by random bits of the interpreter.
+	   All other modules are optional and are initialized
+	   when they are first imported. */
+	
+	initbuiltin(); /* Also initializes builtin exceptions */
+	initsys();
+	
+	initcalls(); /* Configuration-dependent initializations */
+	
+	initintr(); /* For intrcheck() */
+
+	setpythonpath(getpythonpath());
+}
+
+/* Parse input from a file and execute it */
+
+int
+run(fp, filename)
+	FILE *fp;
+	char *filename;
+{
+	if (filename == NULL)
+		filename = "???";
+	if (isatty((int)fileno(fp)))
+		return run_tty_loop(fp, filename);
+	else
+		return run_script(fp, filename);
+}
+
+int
+run_tty_loop(fp, filename)
+	FILE *fp;
+	char *filename;
+{
+	object *v;
+	int ret;
+	v = sysget("ps1");
+	if (v == NULL) {
+		sysset("ps1", v = newstringobject(">>> "));
+		XDECREF(v);
+	}
+	v = sysget("ps2");
+	if (v == NULL) {
+		sysset("ps2", v = newstringobject("... "));
+		XDECREF(v);
+	}
+	for (;;) {
+		ret = run_tty_1(fp, filename);
+#ifdef REF_DEBUG
+		fprintf(stderr, "[%ld refs]\n", ref_total);
+#endif
+		if (ret == E_EOF)
+			return 0;
+		/*
+		if (ret == E_NOMEM)
+			return -1;
+		*/
+	}
+}
+
+int
+run_tty_1(fp, filename)
+	FILE *fp;
+	char *filename;
+{
+	void *save, *save_thread(), restore_thread();
+	object *m, *d, *v, *w;
+	node *n;
+	char *ps1, *ps2;
+	int err;
+	v = sysget("ps1");
+	w = sysget("ps2");
+	if (v != NULL && is_stringobject(v)) {
+		INCREF(v);
+		ps1 = getstringvalue(v);
+	}
+	else {
+		v = NULL;
+		ps1 = "";
+	}
+	if (w != NULL && is_stringobject(w)) {
+		INCREF(w);
+		ps2 = getstringvalue(w);
+	}
+	else {
+		w = NULL;
+		ps2 = "";
+	}
+	save = save_thread();
+	err = parsefile(fp, filename, &gram, single_input, ps1, ps2, &n);
+	restore_thread(save);
+	XDECREF(v);
+	XDECREF(w);
+	if (err == E_EOF)
+		return E_EOF;
+	if (err != E_DONE) {
+		err_input(err);
+		print_error();
+		return err;
+	}
+	m = add_module("__main__");
+	if (m == NULL)
+		return -1;
+	d = getmoduledict(m);
+	v = run_node(n, filename, d, d);
+	flushline();
+	if (v == NULL) {
+		print_error();
+		return -1;
+	}
+	DECREF(v);
+	return 0;
+}
+
+int
+run_script(fp, filename)
+	FILE *fp;
+	char *filename;
+{
+	object *m, *d, *v;
+	m = add_module("__main__");
+	if (m == NULL)
+		return -1;
+	d = getmoduledict(m);
+	v = run_file(fp, filename, file_input, d, d);
+	flushline();
+	if (v == NULL) {
+		print_error();
+		return -1;
+	}
+	DECREF(v);
+	return 0;
+}
+
+int
+run_command(command)
+	char *command;
+{
+	object *m, *d, *v;
+	m = add_module("__main__");
+	if (m == NULL)
+		return -1;
+	d = getmoduledict(m);
+	v = run_string(command, file_input, d, d);
+	flushline();
+	if (v == NULL) {
+		print_error();
+		return -1;
+	}
+	DECREF(v);
+	return 0;
+}
+
+void
+print_error()
+{
+	object *exception, *v;
+	err_get(&exception, &v);
+	if (exception == SystemExit) {
+		if (v == NULL || v == None)
+			goaway(0);
+		if (is_intobject(v))
+			goaway((int)getintvalue(v));
+		else {
+			printobject(v, stderr, PRINT_RAW);
+			fprintf(stderr, "\n");
+			goaway(1);
+		}
+	}
+	sysset("last_type", exception);
+	sysset("last_value", v);
+	if (printobject(exception, stderr, PRINT_RAW) != 0)
+		err_clear();
+	if (v != NULL && v != None) {
+		fprintf(stderr, ": ");
+		if (printobject(v, stderr, PRINT_RAW) != 0)
+			err_clear();
+	}
+	fprintf(stderr, "\n");
+	XDECREF(exception);
+	XDECREF(v);
+	printtraceback(stderr);
+}
+
+object *
+run_string(str, start, globals, locals)
+	char *str;
+	int start;
+	/*dict*/object *globals, *locals;
+{
+	node *n;
+	int err;
+	err = parse_string(str, start, &n);
+	return run_err_node(err, n, "<string>", globals, locals);
+}
+
+object *
+run_file(fp, filename, start, globals, locals)
+	FILE *fp;
+	char *filename;
+	int start;
+	/*dict*/object *globals, *locals;
+{
+	node *n;
+	int err;
+	err = parse_file(fp, filename, start, &n);
+	return run_err_node(err, n, filename, globals, locals);
+}
+
+object *
+run_err_node(err, n, filename, globals, locals)
+	int err;
+	node *n;
+	char *filename;
+	/*dict*/object *globals, *locals;
+{
+	if (err != E_DONE) {
+		err_input(err);
+		return NULL;
+	}
+	return run_node(n, filename, globals, locals);
+}
+
+object *
+run_node(n, filename, globals, locals)
+	node *n;
+	char *filename;
+	/*dict*/object *globals, *locals;
+{
+	if (globals == NULL) {
+		globals = getglobals();
+		if (locals == NULL)
+			locals = getlocals();
+	}
+	else {
+		if (locals == NULL)
+			locals = globals;
+	}
+	return eval_node(n, filename, globals, locals);
+}
+
+object *
+eval_node(n, filename, globals, locals)
+	node *n;
+	char *filename;
+	object *globals;
+	object *locals;
+{
+	codeobject *co;
+	object *v;
+	co = compile(n, filename);
+	freetree(n);
+	if (co == NULL)
+		return NULL;
+	v = eval_code(co, globals, locals, (object *)NULL);
+	DECREF(co);
+	return v;
+}
+
+/* Simplified interface to parsefile */
+
+int
+parse_file(fp, filename, start, n_ret)
+	FILE *fp;
+	char *filename;
+	int start;
+	node **n_ret;
+{
+	return parsefile(fp, filename, &gram, start,
+				(char *)0, (char *)0, n_ret);
+}
+
+/* Simplified interface to parsestring */
+
+int
+parse_string(str, start, n_ret)
+	char *str;
+	int start;
+	node **n_ret;
+{
+	int err = parsestring(str, &gram, start, n_ret);
+	/* Don't confuse early end of string with early end of input */
+	if (err == E_EOF)
+		err = E_SYNTAX;
+	return err;
+}
+
+/* Print fatal error message and abort */
+
+void
+fatal(msg)
+	char *msg;
+{
+	fprintf(stderr, "Fatal error: %s\n", msg);
+	abort();
+}
+
+/* Clean up and exit */
+
+void
+goaway(sts)
+	int sts;
+{
+	flushline();
+	
+	/* XXX Call doneimport() before donecalls(), since donecalls()
+	   calls wdone(), and doneimport() may close windows */
+	doneimport();
+	donecalls();
+	
+	err_clear();
+
+#ifdef REF_DEBUG
+	fprintf(stderr, "[%ld refs]\n", ref_total);
+#endif
+
+#ifdef TRACE_REFS
+	if (askyesno("Print left references?")) {
+		printrefs(stderr);
+	}
+#endif /* TRACE_REFS */
+
+#ifdef USE_THREAD
+	(void) save_thread();
+	exit_prog(sts);
+#else
+	exit(sts);
+#endif
+	/*NOTREACHED*/
+}
+
+#ifdef TRACE_REFS
+/* Ask a yes/no question */
+
+static int
+askyesno(prompt)
+	char *prompt;
+{
+	char buf[256];
+	
+	printf("%s [ny] ", prompt);
+	if (fgets(buf, sizeof buf, stdin) == NULL)
+		return 0;
+	return buf[0] == 'y' || buf[0] == 'Y';
+}
+#endif
+
+#ifdef applec /* MPW (also usable for Think C 3.0) */
+
+/* Check for file descriptor connected to interactive device.
+   Pretend that stdin is always interactive, other files never. */
+
+int
+isatty(fd)
+	int fd;
+{
+	return fd == fileno(stdin);
+}
+
+#endif