Python/pythonrun.c - platform/external/python/cpython2 - Gitiles

 /***********************************************************
 Copyright 1991, 1992, 1993 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 "eval.h"
 #include "ceval.h"
 #include "pythonrun.h"
 #include "import.h"

 #ifdef unix
 #define HANDLE_SIGNALS
 #endif

 #ifdef HANDLE_SIGNALS
 #include <signal.h>
 #include "sigtype.h"
 #endif

 extern char *getpythonpath();

 extern grammar gram; /* From graminit.c */

 /* Forward */
 static object *run_err_node PROTO((int err, node *n, char *filename,
 				   object *globals, object *locals));
 static object *run_node PROTO((node *n, char *filename,
 			       object *globals, object *locals));
 static object *eval_node PROTO((node *n, char *filename,
 				object *globals, object *locals));
 static void initsigs PROTO((void));

 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 */

 	setpythonpath(getpythonpath());

 	initsigs(); /* Signal handling stuff, including initintr() */
 }

 /* 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;
 {
 	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 = "";
 	}
 	BGN_SAVE
 	err = parsefile(fp, filename, &gram, single_input, ps1, ps2, &n);
 	END_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, *f;
 	err_get(&exception, &v);
 	if (exception == SystemExit) {
 		if (v == NULL || v == None)
 			goaway(0);
 		if (is_intobject(v))
 			goaway((int)getintvalue(v));
 		else {
 			/* OK to use real stderr here */
 			printobject(v, stderr, PRINT_RAW);
 			fprintf(stderr, "\n");
 			goaway(1);
 		}
 	}
 	sysset("last_type", exception);
 	sysset("last_value", v);
 	f = sysget("stderr");
 	if (f == NULL)
 		fprintf(stderr, "lost sys.stderr\n");
 	else {
 		printtraceback(f);
 		if (writeobject(exception, f, PRINT_RAW) != 0)
 			err_clear();
 		if (v != NULL && v != None) {
 			writestring(": ", f);
 			if (writeobject(v, f, PRINT_RAW) != 0)
 				err_clear();
 		}
 		writestring("\n", f);
 	}
 	XDECREF(exception);
 	XDECREF(v);
 }

 object *
 run_string(str, start, globals, locals)
 	char *str;
 	int start;
 	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;
 	object *globals, *locals;
 {
 	node *n;
 	int err;
 	err = parse_file(fp, filename, start, &n);
 	return run_err_node(err, n, filename, globals, locals);
 }

 static object *
 run_err_node(err, n, filename, globals, locals)
 	int err;
 	node *n;
 	char *filename;
 	object *globals, *locals;
 {
 	if (err != E_DONE) {
 		err_input(err);
 		return NULL;
 	}
 	return run_node(n, filename, globals, locals);
 }

 static object *
 run_node(n, filename, globals, locals)
 	node *n;
 	char *filename;
 	object *globals, *locals;
 {
 	return eval_node(n, filename, globals, locals);
 }

 static 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, (object *)NULL);
 	DECREF(co);
 	return v;
 }

 object *
 compile_string(str, filename, start)
 	char *str;
 	char *filename;
 	int start;
 {
 	node *n;
 	int err;
 	codeobject *co;
 	err = parse_string(str, start, &n);
 	if (err != E_DONE) {
 		err_input(err);
 		return NULL;
 	}
 	co = compile(n, filename);
 	freetree(n);
 	return (object *)co;
 }

 /* Simplified interface to parsefile */

 int
 parse_file(fp, filename, start, n_ret)
 	FILE *fp;
 	char *filename;
 	int start;
 	node **n_ret;
 {
 	int ret;
 	BGN_SAVE
 	ret = parsefile(fp, filename, &gram, start,
 				(char *)0, (char *)0, n_ret);
 	END_SAVE
 	return 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 */

 #ifdef USE_THREAD
 extern int threads_started;
 #endif

 static void
 cleanup()
 {
 	object *exitfunc = sysget("exitfunc");

 	if (exitfunc) {
 		object *arg;
 		object *res;
 		sysset("exitfunc", (object *)NULL);
 		arg = newtupleobject(0);
 		if (arg == NULL)
 			res = NULL;
 		else {
 			res = call_object(exitfunc, arg);
 			DECREF(arg);
 		}
 		if (res == NULL) {
 			fprintf(stderr, "Error in sys.exitfunc:\n");
 			print_error();
 		}
 	}

 	flushline();
 }

 #ifdef COUNT_ALLOCS
 extern void dump_counts PROTO((void));
 #endif

 void
 goaway(sts)
 	int sts;
 {
 	cleanup();

 #ifdef COUNT_ALLOCS
 	dump_counts();
 #endif

 #ifdef USE_THREAD

 	/* Other threads may still be active, so skip most of the
 	   cleanup actions usually done (these are mostly for
 	   debugging anyway). */

 	(void) save_thread();
 	donecalls();
 	if (threads_started)
 		_exit_prog(sts);
 	else
 		exit_prog(sts);

 #else /* USE_THREAD */

 	/* 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 */

 	exit(sts);
 #endif /* USE_THREAD */
 	/*NOTREACHED*/
 }

 #ifdef HANDLE_SIGNALS
 static SIGTYPE
 sighandler(sig)
 	int sig;
 {
 	signal(sig, SIG_DFL); /* Don't catch recursive signals */
 	cleanup(); /* Do essential clean-up */
 	kill(getpid(), sig); /* Pretend the signal killed us */
 	/*NOTREACHED*/
 }
 #endif

 static void
 initsigs()
 {
 	initintr();
 #ifdef HANDLE_SIGNALS
 	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
 		signal(SIGHUP, sighandler);
 	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
 		signal(SIGTERM, sighandler);
 #endif
 }

 #ifdef TRACE_REFS
 /* Ask a yes/no question */

 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
	/***********************************************************
	Copyright 1991, 1992, 1993 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 "eval.h"
	#include "ceval.h"
	#include "pythonrun.h"
	#include "import.h"

	#ifdef unix
	#define HANDLE_SIGNALS
	#endif

	#ifdef HANDLE_SIGNALS
	#include <signal.h>
	#include "sigtype.h"
	#endif

	extern char *getpythonpath();

	extern grammar gram; /* From graminit.c */

	/* Forward */
	static object run_err_node PROTO((int err, node n, char *filename,
	object globals, object locals));
	static object run_node PROTO((node n, char *filename,
	object globals, object locals));
	static object eval_node PROTO((node n, char *filename,
	object globals, object locals));
	static void initsigs PROTO((void));

	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 */

	setpythonpath(getpythonpath());

	initsigs(); /* Signal handling stuff, including initintr() */
	}

	/* 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;
	{
	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 = "";
	}
	BGN_SAVE
	err = parsefile(fp, filename, &gram, single_input, ps1, ps2, &n);
	END_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, *f;
	err_get(&exception, &v);
	if (exception == SystemExit) {
	if (v == NULL \|\| v == None)
	goaway(0);
	if (is_intobject(v))
	goaway((int)getintvalue(v));
	else {
	/* OK to use real stderr here */
	printobject(v, stderr, PRINT_RAW);
	fprintf(stderr, "\n");
	goaway(1);
	}
	}
	sysset("last_type", exception);
	sysset("last_value", v);
	f = sysget("stderr");
	if (f == NULL)
	fprintf(stderr, "lost sys.stderr\n");
	else {
	printtraceback(f);
	if (writeobject(exception, f, PRINT_RAW) != 0)
	err_clear();
	if (v != NULL && v != None) {
	writestring(": ", f);
	if (writeobject(v, f, PRINT_RAW) != 0)
	err_clear();
	}
	writestring("\n", f);
	}
	XDECREF(exception);
	XDECREF(v);
	}

	object *
	run_string(str, start, globals, locals)
	char *str;
	int start;
	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;
	object globals, locals;
	{
	node *n;
	int err;
	err = parse_file(fp, filename, start, &n);
	return run_err_node(err, n, filename, globals, locals);
	}

	static object *
	run_err_node(err, n, filename, globals, locals)
	int err;
	node *n;
	char *filename;
	object globals, locals;
	{
	if (err != E_DONE) {
	err_input(err);
	return NULL;
	}
	return run_node(n, filename, globals, locals);
	}

	static object *
	run_node(n, filename, globals, locals)
	node *n;
	char *filename;
	object globals, locals;
	{
	return eval_node(n, filename, globals, locals);
	}

	static 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, (object )NULL);
	DECREF(co);
	return v;
	}

	object *
	compile_string(str, filename, start)
	char *str;
	char *filename;
	int start;
	{
	node *n;
	int err;
	codeobject *co;
	err = parse_string(str, start, &n);
	if (err != E_DONE) {
	err_input(err);
	return NULL;
	}
	co = compile(n, filename);
	freetree(n);
	return (object *)co;
	}

	/* Simplified interface to parsefile */

	int
	parse_file(fp, filename, start, n_ret)
	FILE *fp;
	char *filename;
	int start;
	node **n_ret;
	{
	int ret;
	BGN_SAVE
	ret = parsefile(fp, filename, &gram, start,
	(char )0, (char )0, n_ret);
	END_SAVE
	return 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 */

	#ifdef USE_THREAD
	extern int threads_started;
	#endif

	static void
	cleanup()
	{
	object *exitfunc = sysget("exitfunc");

	if (exitfunc) {
	object *arg;
	object *res;
	sysset("exitfunc", (object *)NULL);
	arg = newtupleobject(0);
	if (arg == NULL)
	res = NULL;
	else {
	res = call_object(exitfunc, arg);
	DECREF(arg);
	}
	if (res == NULL) {
	fprintf(stderr, "Error in sys.exitfunc:\n");
	print_error();
	}
	}

	flushline();
	}

	#ifdef COUNT_ALLOCS
	extern void dump_counts PROTO((void));
	#endif

	void
	goaway(sts)
	int sts;
	{
	cleanup();

	#ifdef COUNT_ALLOCS
	dump_counts();
	#endif

	#ifdef USE_THREAD

	/* Other threads may still be active, so skip most of the
	cleanup actions usually done (these are mostly for
	debugging anyway). */

	(void) save_thread();
	donecalls();
	if (threads_started)
	_exit_prog(sts);
	else
	exit_prog(sts);

	#else /* USE_THREAD */

	/* 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 */

	exit(sts);
	#endif /* USE_THREAD */
	/NOTREACHED/
	}

	#ifdef HANDLE_SIGNALS
	static SIGTYPE
	sighandler(sig)
	int sig;
	{
	signal(sig, SIG_DFL); /* Don't catch recursive signals */
	cleanup(); /* Do essential clean-up */
	kill(getpid(), sig); /* Pretend the signal killed us */
	/NOTREACHED/
	}
	#endif

	static void
	initsigs()
	{
	initintr();
	#ifdef HANDLE_SIGNALS
	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
	signal(SIGHUP, sighandler);
	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
	signal(SIGTERM, sighandler);
	#endif
	}

	#ifdef TRACE_REFS
	/* Ask a yes/no question */

	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