Two changes to from...import: 1) "from M import X" now works even if M is not a real module; it's basically a getattr() operation with AttributeError exceptions changed into ImportError. 2) "from M import *" now looks for M.__all__ to decide which names to import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but filters out names starting with '_' as before. Whether or not __all__ exists, there's no restriction on the type of M.

/* PD implementation of strerror() for systems that don't have it.
   Author: Guido van Rossum, CWI Amsterdam, Oct. 1990, <guido@cwi.nl>. */

#include <stdio.h>

extern int sys_nerr;
extern char *sys_errlist[];

char *
strerror(int err)
{
	static char buf[20];
	if (err >= 0 && err < sys_nerr)
		return sys_errlist[err];
	sprintf(buf, "Unknown errno %d", err);
	return buf;
}

#ifdef macintosh
int sys_nerr = 0;
char *sys_errlist[1] = 0;
#endif