Binary I/O on stdin/stdout?

[Doug Gwyn]

In article <8036 at elsie.UUCP> ado at elsie.UUCP (Arthur David Olson) writes:
>Couldn't freopen simply return ((FILE *) 0) in such cases, much as
>localtime is allowed to return -1 if local time can't be determined?

Sure; but then what good does it to to specify the facility if
portable code couldn't rely on it working?