patch to check for page breaks and use with error (BSD)

[Richard A. O'Keefe]

In the function error() in main.c, change
	exit(errors);
to	exit(errors == 0 ? 0 : 1);

This is because 256 errors looks exactly like 0 errors in UNIX systems...

In the function main() in main.c, change
	return errors;
to	exit(errors == 0 ? 0 : 1);

This is for the same reason.